Gemstones

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Know Your Stones - Buy Only Quality - Make A Smart Investment

Stones are listed in alphabetical order. Links to information about American turquoise mines can be found under the turquoise heading on this page. We will continue to add more samples of gemstones in the future.

AGATE

Agate is a member of the Chalcedony species. It's distinctive concentric, banded, shell-like appearance is sometimes enhanced by dying the stone. The bands within this stone are usually multicolored, consisting of fine quartz fibers. Some deposits have a variety of strong to soft color variations like those that had been found in Germany, while others, like the Brazilian Agate, have naturally dull gray bands for which dying will create a more dramatic effect. Since the dye will be absorbed with different intensity, depending on the composition of the bands, it is very difficult to tell the difference between it and naturally colored agate, unless the color used rarely appears normally in nature.

Agate is found as a ball or oblong nodule that can range in size from a fraction of an inch to several yards in circumference. Initial important deposit finds in Germany have been pretty much worked out, but reserves remain in Brazil and northern Uruguay. Other deposits also exist in Australia, China, India, Mexico, Madagascar, Nambia and the states of Idaho, Oregon, Utah, Washington, Wyoming and Montana in the United States.

AMAZONITE

This green sodium feldspar has derived it's name from one of it's origins. Or perhaps it's green color conjured up images of the lush green forests of the Amazon, but there are deposits taken from Brazil. This stone can be found in China, India, Kenya, Madagascar, Namibia, Russia and the state of Colorado and Nevada in the United States.

Amazonite is generally opaque and can be sensitive to pressure. It is sometimes confused for Chrysoprase, Jade or Serpentine.

AMBER

Chemistry: Approximately C10H16O; Succinic acid.
Class: Mineraloids
Uses: Ornamental stone, gemstone and semi-precious stone.
The Physical Properties of Amber.
Specimens
Amber, or fossil tree sap, was made famous in the movie "Jurassic Park". Amber is a beautiful stone that is cut and polished and used as a valuable gemstone. It is also a fossil and can contain many preserved insects and other animals and plants that are tens of millions of years old. The odd inclusions that are often seen in amber usually add to amber's unique look and in many cases greatly increase its value.
The fossils that are encased in amber probably got there when they flew or crawled on to the fresh seeping sap and then got stuck. The sap oozed over the trapped animals and perhaps fell to the ground and was later covered by dirt and debris. The sap later hardened and became a fossil.

The fossils are mostly insects such as gnats, flies, wasps, bees and ants. Occasionally more exotic insects are trapped in the amber such as grasshoppers, preying mantises, beetles, moths, termites, butterflies, etc. Other non-insect animals are found in amber too such as spiders, centipedes, scorpions and even frogs and lizards. No really large animals like mammals or birds are seen in amber but feathers and fur have been seen. Invaluable plant remains have also been found in amber including flowers, mushroom caps, seeds, leaves, stems, pine needles and pine cones. The rarity of the trapped fossils controls the value of the amber more so than the quality of the amber. Remember these are fossils and are not the same species that are alive today. Amber has greatly increased the knowledge of the evolution of insects and plants as well as enlivening the interest in paleontology in general.

Amber is often imitated by plastics, colored glasses and some modern tree resins. However, its hardness is usually greater and it is tougher than other resins. Its low specific gravity (amber can float on salt water) and inclusions can distinguish it from plastics and glasses.

PHYSICAL CHARACTERISTICS:
Color is amber yellow to orange.
Luster is resinous.
Transparency: Transparent to translucent.
Crystal System does not apply because amber is amorphous (meaning it does not have an ordered structure).
Habits include nodules embedded in shales or sandstones and those that are washed up on beaches.
Fracture is conchoidal.
Hardness is 2+.
Specific Gravity is approximately 1.1 (extremely light and can float in salty water).
Streak is white.
Other Characteristics: Can be burned, fluorescent under UV light and is much tougher (will not crumble as easily) than modern tree resins.
Notable Occurrences include all Baltic countries; Venezuela; Russia; Romania; Burma; in coal seams in Wyoming, USA and the Dominican Republic.
Best Field Indicators are color, density, toughness, softness and trapped insects.

AMETHYST

Amethyst, a transparent purple variety of quartz, is one of the best known and most valuable forms of quartz. The name “amethyst” comes from the Greek and means “not drunken”. It was once thought to prevent the wearer from getting drunk and also thought to bring peace of mind.

Amethyst is purple and ranges from light to dark which is caused by iron or manganese compound impurities in the mineral. Amethyst comes from many parts of the world and each locality can produce a unique amethyst to that area or particular mine.

The following is a list of many of the more noteworthy localities and some of the attributes that characterize the amethyst found there.

Vera Cruz, Mexico -- very pale, clear, prismatic crystals that are sometimes double terminated and have grown on a light colored host rock. Crystals are typically phantomed, having a clear quartz interior and an amethyst exterior. Some are sceptered and phantomed.

Guerrero, Mexico -- dark, deep purple, prismatic crystals that radiate outward from a common attachment point. Often the crystals are phantomed opposite of Vera Cruz amethyst having a purple interior with a clear or white quartz exterior. These are some of the most valuable amethysts in the world.

Minas Gerais and Rio Grande do Sul, Bahaia, Brazil -- crystals form in druzy crusts that line the inside of sometimes large volcanic rock pockets or "vugs". Some of the vugs form from trees that were engulfed in a lava flow millions of years ago and have since withered away. Other vugs are just gas bubbles in the lava. Some vugs can be quite large. The crystals that form are usually light to medium in color and only colored at the tops of the crystals. Most clusters form with gray, white and blue agate and have a green exterior on the vugs. Calcite sometimes is associated and inclusions of cacoxenite are common.

Maraba, Brazil -- large crystals with unattractive surfaces that are of a pale to medium color and often carved or cut into slices.

Thunder Bay, Canada -- a distinct red hematite inclusion just below the surface of the crystals is unique to this locality. Clusters are druzy crusts that line the fissures formed in ancient metamorphic rocks.

Uruguay -- crystals are dark to medium and form in druzy crusts that line the inside of volcanic vugs that have a gray or brown exterior. The crystals are usually colored throughout, unlike the Brazilian crystals, and form with a multicolored agate that often contains reds, yellows and oranges. Often amethyst- coated stalactites and other unusual formations occur inside these vugs.

Africa -- crystals are usually large but not attractive. However, the interior color and clarity are excellent and polished slices and carvings as well as many gemstones are prized and admired.

Maine, USA -- Dark druzy clusters that are not widely distributed today.

North Carolina, USA -- Druzy clusters that have a bluish-violet tint.

Pennsylvania, USA -- druzy clusters that filled fractures in metamorphic rocks. They are generally a brownish purple and patchy in color.

Colorado, USA -- druzy clusters form crusts inside of fissures in sandstone, often on top of a crust of green fluorite. Crystals are dark but rather small.

Italy -- both Vera Cruz like crystals, although not as well defined, and large parallel growth clusters with good evenly distributed color.

Germany -- associated with colorful agates that form a druzy light-colored crust.
Ural Mountains, Russia -- a very clear and dark variety that is cut for fine expensive gemstones, natural uncut clusters are rarely on the market.

Variety of: Quartz , SiO2 .
Uses: Gemstones and ornamental stones.
Birthstone for: February
Color: various shades of purple.
Index of refraction: 1.544-1.553
Birefringence: 0.009
Hardness: 7
Cleavage: none
Crystal system: trigonal
Pleochroic: no

AMMONITE

Ammonites are the fossilized, hard shells of extinct mollusks that existed from the Paleozoic to the end of the Cretaceous era. They were abundant in all the oceans. Their closest relative is the chambered Nautilus from the Pacific and Indian oceans. After millions of years the original shell is slowly replaced by minerals such as agate or calcite. Ammonite fossils are found on every continent. They are treasured for their appearance and form. Some show very intricate suture patterns, which are created by the complex walls dividing the inside of the shell.

The Navajos and other Native American Indian tribes carried ammonites in their medicine bags for health and good hunting. They were called Buffalo stones because of their resemblance to the North American Bison.

ANYOLITE

Anyolite is a member of the Zoisite species. Usually opaque rubies occurring within green zoisite rock with black hornblende inclusions. It's colorful variations make it a beautiful specimen. The first known discovery was in Tanzania in 1954.

ALEXANDRITE

Alexandrite is a variety of the Chrysoberyl species. It's name is derived from the Russian Czar, Alexander the 2nd who was in power when it was discovered in the 1830s. It's color changing properties, dependant on the light source, are what makes this gemstone unique, and sought after. Larger specimens show their color changing properties best and can be very expensive. Sunlight changes it's hue to green, while showing influences of light red under artificial incandescent light sources.

Although originally discovered in the Urals, that supply has been essentially depleted. Currently mined from Zimbabwe, Sri Lanka and most recently from Brazil. Smaller deposits have also been found in Tanzania, Burma and Madagascar.

Primarily fashioned into faceted gemstones, Alexandrite can be quite expensive. Chemically identical lab created gems are available, having the same color changing properties for considerably less cost. This should not be confused with an artificial gemstone called "Zandrite" which boasts complete color changing properties, but is essentially a specially treated glass.

APATITE

Found in many colors, but green is most common. Can be sensitive to acids. Transparent to somewhat opaque, it has a vitreous luster.

Chemistry: Ca5(PO4)3(OH,F,Cl), Calcium (Fluoro, Chloro, Hydroxyl) Phosphate
Class: Phosphates
Group: Apatite
Uses: as a source of phosphorous to be used in fertilizer, rarely as a gemstone and as a mineral specimen.
Specimens
Apatite is actually three different minerals depending on the predominance of either fluorine, chlorine or the hydroxyl group. These ions can freely substitute in the crystal lattice and all three are usually present in every specimen although some specimens have been close to 100% in one or the other. The rather non-inventive names of these minerals are Fluorapatite, Chlorapatite and Hydroxylapatite. The three are usually considered together due to the difficulty in distinguishing them in hand samples using ordinary methods.
An irony of the name apatite is that apatite is the mineral that makes up the teeth in all vertebrate animals as well as their bones. Get it? Apatite - teeth! Anyway, the name apatite comes from a Greek word meaning to decieve in allusion to its similarity to other more valuable minerals such as olivine, peridot and beryl.

Apatite is widely distributed in all rock types; igneous, sedimentary and metamorphic, but is usually just small disseminated grains or cryptocrystalline fragments. Large well formed crystals though can be found in certain contact metamorphic rocks. Very gemmy crystals of apatite can be cut as gems but the softness of apatite prevents wide distribution or acceptance of apatite as a gemstone.

PHYSICAL CHARACTERISTICS:
Color is typically green but also yellow, blue, reddish brown and purple.
Luster is vitreous to greasy and gumdrop.
Transparency: Crystals are transparent to translucent.
Crystal System is hexagonal; 6/m
Crystal Habits include the typical hexagonal prism with the hexagonal pyramid or a pinacoid or both as a termination. Also accicular, granular, reniform and massive. A cryptocrystalline variety is called collophane and can make up a rock type called phosphorite and also can replace fossil fragments.
Cleavage is indistinct in one basal direction.
Fracture is conchoidal.
Hardness is 5.
Specific Gravity is approximately 3.1 - 3.2 (average for translucent minerals)
Streak is white.
Associated Minerals are hornblende, micas, nepheline and calcite.
Other Characteristics: An unusual "partially dissolved" look similar to the look of previously sucked on hard candy.
Notable Occurrences include Durango, Mexico; Bancroft, Ontario; Germany Brazil, Burma, India, Madagascar, Kenya, Mexico, Norway, South Africa, Norway, The United States and Russia.

Best Field Indicators are crystal habit, color, hardness and look.

AQUAMARINE - Colorado's State Stone

It's name means "water of the sea" in Latin because it's color so resembles that of ocean water. Iron creates this color naturally in this stone, but heating specimens with lower iron content will bring out the desired color permanently. When overheated though, it can lead to discoloration. Attempts to improve color with gamma and neutron irradiation can be done, but the changes aren't permanent. Aquamarine can make beautiful faceted gemstones, but jewelers must be very careful when using it for their creations because it can be brittle. It is also sensitive to pressure. Aquamarine is Colorado's state stone. It is the birthstone for March.

AVENTURINE QUARTZ

Found primarily in dark green with occasional glittery metallic inclusions of green mica or gold-brown to red caused by hematite particles.

Sources are India, Austria, Brazil, Russia and Tanzania. Used by making into cabochons and carved figurines for jewelry and ornamental items.

AVENTURINE FELDSPAR - "Sunstone"

Aventurine Feldspar (oligoclase), is opaque with glittery gold or red inclusions. Rare occurrences of green or blue glitter are sometimes found. The inclusions causing the sparkle are actually reflections from minute goethite or hematite platelets.

There are deposits found in India, Madagascar, Norway, Canada, Russia and the United States. Generally used by forming into cabochons or other flat surfaces for jewelry.

AZURITE

Chemistry: Cu3(CO3)2(OH)2, Copper Carbonate Hydroxide
Class: Carbonates
Uses: ornamental stone, pigment, minor ore of copper, and jewelry.
Specimens
Azurite is a very popular mineral because of its unparalleled color, a deep blue called "azure", hence its name. Azure is derived from the arabic word for blue. The color is due to the presence of copper (a strong coloring agent), and the way the copper chemically combines with the carbonate groups (CO3) and hydroxyls (OH). Azurite has been used as a dye for paints and fabrics for eons. Unfortunately, at times its color is too deep and larger crystals can appear black. Small crystals and crusts show the lighter azure color well. Azurite is often associated with its colorful close cousin, malachite
Green malachite is closely associated with azurite in many ways. Not only do they frequently occur together (pictured above), they also have very similar formulae. Malachite can also replace azurite, making a pseudomorph, or an exact copy of an azurite crystal (only now instead of being blue, it would be green). Compare their formulas:

Azurite's formula: Cu3(CO3)2(OH)2

Malachite's formula: Cu2(CO3)(OH)2

The charges on the copper ions are the same for both minerals at positive two (each hydroxide has a charge of negative one and each carbonate has a charge of negative two). But what causes the color change from azurite to malachite if the charge on the copper remains the same? Consider the formulas if they are rewritten as so:

Azurite's formula: Cu(OH)2-2(CuCO3)

Malachite's formula: Cu(OH)2-CuCO3

Notice the different amounts of CuCO3 in the two formulas. The azurite seems to have an extra CuCO3, but the transformation could be explained by an addition of an extra Cu(OH)2 to azurite's formula to make two malachites as in the following equation:

Cu(OH)2-2(CuCO3) + Cu(OH)2 ----> 2{Cu(OH)2-CuCO3}
{AZURITE} 2{MALACHITE}
Since the Cu(OH)2 is more oxidized than the CuCO3, the malachite is therefore more oxidized than azurite. This means that malachite represents a later stage of oxidation and the increased oxidation is what causes the color change. The actual formula for the conversion is a bit more involved and includes the addition of a water molecule to two azurite molecules and the release of a carbon dioxide molecule; leaving behind three malachite molecules. The equation is represented as follows:

2{Cu(OH)2-2(CuCO3)} + H2O ---------> 3{Cu(OH)2-CuCO3} + CO2
2{AZURITE} {WATER} 3{MALACHITE} {CARBON DIOXIDE}

The oxidation is persistent and actually ongoing, although very slow. Azurite paints made centuries ago have undergone the transformation much to the imagined horror of artists whose paintings of beautiful blue skies now have a most unusual green hue! Thankfully for mineralogists and collectors, this transformation is one of the most asthetically pleasing in the mineral kingdom. Although the malachite may soften the sharpness of the azurite crystal, it generally leaves the specimen intact and a whole range of transformations from pure azurite to pure malachite can be obtained. There really is no comparison to any other mineral to mineral transformation in terms of overall beauty.

Azurite is used in jewelry and for dyes as mentioned above. It is also an unimportant ore of copper, although its significance has been more impressive in the past. It is still considered a minor ore of copper; mostly because it is found associated with other more valuable copper ores. Fine crystal clusters, nodular specimens, and interesting and beautiful combinations with malachite are important pieces in anyone's mineral collection. The magnificent color of azurite is worth mentioning again as it truly is a one-of-a-kind in the mineral world. Azurite is one of those classic minerals.

PHYSICAL CHARACTERISTICS:
Color is azure, deep blue or pale blue if found in small crystals or crusts.
Luster is vitreous to dull depending on habit.
Transparency: Transparent if in thin crystals, otherwise translucent to opaque.
Crystal System is monoclinic; 2/m.
Crystal Habits crystals are irregular blades with wedge shaped terminations. Also, aggregate crusts and radiating, botryoidal, nodular and earthy masses.
Cleavage is good in one direction and fair in another.
Fracture is conchoidal and brittle.
Hardness is 3.5-4.
Specific Gravity is 3.7+ (heavier than average).
Streak is blue.
Associated Minerals are numerous and include malachite limonite, calcite, cerussite, quartz, chalcopyrite, native copper, cuprite, chrysocolla, aurichalcite, shattuckite, liroconite, connellite and other oxidized copper minerals.
Notable Occurrences include numerous localities worldwide, but special localities produce some outstanding specimens especially from Lasal, Utah; Bisbee, Arizona and New Mexico, USA; Mexico; Tsumeb, Nambia; Shaba, Congo; Toussit, Morocco; Australia and in many locations in Europe.
Best Field Indicators are color, softness, crystal habits and associations.

CARNELIAN

A member of the Chalcedonly species, Carnelian is thought to have been named after the color of the kornel cherry which it likens too. Orange to brownish-red with varieties having some translucency to opaque qualities. Iron contained within the stone gives it this coloring, but heat can enhance it too. Color within this stone is generally dispersed in cloudy patterns.

Found in Brazil, Uruguay and India.

CHROME DIOPSIDE

It sounds more like an ingredient a chemist would use rather than a jeweler, but this gemstone is a striking emerald green color. Can react negatively to hydroflouric acid. Will actually melt under a jeweler's torch.

Diopside is russian chrome diopside value a diopside chrome diopside jewelry rough monoclinic chrome diopside diopside mines included pyroxene mineral with composition star diopside MgCaSi2O6. It forms a solid solution series with hedenbergite (FeCaSi2O6) and augite. Diopside is found in mafic igneous rocks as well as in many metamorphic rocks. It is also a constituent of the Earth's mantle.

Gemstone quality diopside is found diopside in two forms: diopside stone the black chrome diopside wholesale what is black star diopside star diopside and the chrome diopside (which includes chromium giving chrome diopside russian diopside chrome diopside beads diopside in greece it a green colour).

Most deposits are found primarily in Russia and Kenya.

CHAROLITE – CHAROITE

Charoite is a relatively late comer to the marketplace, having been known only since the mid 1970’s. The color of charoite is described as a stunning lavender, lilac, violet or purple. The white chrystalline “needles” give charoite a very distinctive appearance and depth often forming a swirling pattern of interlocking crystals. Charoite is found in the inerfluve of the Chara and Tokkin rivers, northwest of Aldan on the Jakutsk area, northeast of Lake Baikal, Russia.

CHRYSOPRASE

Chrysoprase is a highly translucent, bright, light green to dark green valuable form of chalcedony. The stone’s vivid green color comes from nickel silicate. It is usually cut into cabochons. This stone is mined exclusively in Australia and is sometimes confused with jade and called “Australian jade”.

CITRINE

Citrine is a member of the Quartz species. It is so named due to it's lemon yellow color. Colored by it's iron content, natural specimens are quite rare. Commercial Citrines these days are most likely heat treated Amethyst or Smoky Quartz. Mostly all of heat treated citrines have a slight reddish tint to them. Pale yellow generally denotes a natural stone.

Natural-colored citrines are mined from Madagascar, Brazil, Argentina, Burma, Namibia, Russia, Scotland, Spain and the United States.

MEDITERRANEAN CORAL

Coral is one of the world’s few organic gems. The oldest known findings of red coral date from the Mesopotamian civilization from about 3000 B.C. Coral is formed from a colony of marine invertebrates, primarily a skeletal calcium carbonate gem. The formations as seen in the water look like tree branches. Many colors and varieties of coral are found in warm coastal waters from around the world. Coral varies in color: white, pink, orange, red and black. The rarest variety is the blood coral or oxblood coral. This is a very deep red variety. The best oxblood coral comes from the Mediterranean Sea. Coral is usually cabochon cut. Because of its calcium composition coral should not come in contact with acid such as vinegar.

DIAMONDS

Probably the best known gemstone in the world, diamonds have long since been a very valuable item to own. So hard that it constitutes the highest range of "10" on the Mohs' Hardness Scale. Diamond chips that are not of gem quality are often used for the tips of drill bits because of their durability. This hardness is one reason that jewelers find this one of the most difficult gems to cut into a faceted stone, but also one of the most profitable.

A wonderfully beautiful stone when faceted, the refractions from it's many possible cuts make it a favorite of jewelers and customers the world over.

In the past, because of their high cost, many diamond imitations have been tried to duplicate the look for a lesser cost. Natural Zircons were often used as well as other natural colorless specimens of rock crystal, precious beryl, topaz and sapphire to imitate the look or deceive unsuspecting buyers. A most common alternative these days is the lab created Cubic Zirconia, which is shown in the picture above, as it can closely resemble colorless diamonds for a fraction of the cost.

Natural diamonds can be found in a variety of colors. While colorless diamonds are the most valuable, natural colored diamonds can increase value if it is one of the rarer colors of green, red, blue or purple. Yellow diamonds are the most common color found and are sometimes referred to in the trade as "champagne" diamonds.

Diamonds are graded for things like color, clarity, and cut. Inclusions will affect clarity and generally degrade the perceived quality of the stone. The cut of a diamond also affects the price as the complexity of the cut will generally produce a better, more dazzling look, but does add to the cost of preparing the stone.

Naturally colored diamonds are more valuable than treated ones, but treatments like irradiation can change lesser quality diamonds with multiple inclusions into more usable specimens for jewelry.

EMERALD

Emeralds are a member of the Beryl species. Considered a precious stone, it's name has become synonymous with the deep rich green color for which it is known. Chrome contained within is responsible for it's brilliant coloring.

The very best emerald specimens are transparent, but many are clouded by inclusions. Although all emeralds are brittle, stones can be facetted, and most times are. Clear Emerald specimens are very valueable.

FLOURITE CRYSTAL

Flourite crystals, sometimes called Fluorspar, shows banded color distribution as seen in the rainbow Flourite Crystals pictured above.

Found in Germany, Burma, Argentina, England, France, Namibia, Austria, Switzerland and the state of Illinois in the United States.

Fossil Mammoth Ivory

Among the treasures hidden for thousands of years in the remote Arctic tundra of Alaska, Canada and Siberia are the massive ivory tusks of the Woolly Mammoth, ruler of the prehistoric savanna. Larger than today's Indian elephant, their tusks could weigh up to 300 pounds each and measure over 16 feet in length. These great beasts ultimately succumbed to the drastic climate changes accompanying great ice ages. The skeletons and tusks were naturally interred for aeons in the frozen earth. We bring this hidden treasure to you as a beautiful gem alternative to new elephant ivory.

These massive tusks are unearthed many ways. Modern day gold miners dredge up mineralized remains in the course of placer mining activities. We unearth fossil ivory during road construction. Bush pilots spot the huge tusks jutting from ever eroding river banks while flying over the tundra. Wilderness explorers find the tusks in the melting muskeg. Regardless of the happy surprise of discovery, all of our ivory is mined in accordance with all applicable federal and state regulations.

The beautiful hues of tan, brown and blue are a result of thousands of years of mineralization. Exact hues depend upon the mineral deposits in the immediate soil surrounding the fallen mammoth. Thus, when processing, each tusk reveals a unique character, never duplicated in another piece of fossil tusks.

International trade in elephant ivory has been largely shut down due to concern for the preservation of a living species. Much to the delight of fine jewelry collectors, fossil mammoth ivory has emerged as an eco-friendly and increasingly valuable alternative. While still scarce and difficult to work with, this lustrous natural ivory possesses the same gem qualities of new ivory, without the stigma attached to illegal harvesting of endangered elephants.

Our supplier has searched out these prized fossils to transform the ancient ivory into lustrous jewelry that reflect the hues of the Arctic landscape. Their skilled craftsmen in Hong Kong, an internationally recognized center for ivory carving, carefully work with the fragile tusks. Each item is painstakingly designed, carved, polished and finished to enhance the unique color of our Arctic Ivory. As with all fine gem quality ivory, the luster is enhanced with frequent exposure to one's natural skin oils, developing a rich patina over time.

FOSSILIZED CORAL REEF

The differential nature of uplifted fossilized coral reef on the western end of Roatan Island, Honduras is representative of the ongoing earthquake activity of subsidiary faults along the American/Caribbean plate boundary in Central America. Surveying elevations and mapping the distribution of fringing coral reefs, fossil reefs, wave cut terraces, exposed beach rock, beach sediments, and cave dripstones that have been uplifted and/or tilted by fault movements was performed in an area of approximately 10km2. At five dispersed locations subsurface samples were taken down to a depth of 2.5m. These samples were analyzed by XRD and ESR at intervals of 20cm. Ohio State University’s Nuclear Reactor Lab analyzed selected samples for U, Th, and K content, and also irradiated annealed samples at six intervals of intensity. The irradiated samples were used to establish a regression curve of radiation exposure to ESR signal. Using radionuclide content and this regression curve, ESR signals of field samples were analyzed to estimate their crystallization and/or recrystallization ages. All ESR signals of the field samples were below the limit of resolution of the regression curve (i.e. >20k years). Recrystallization of the coral may have accompanied differential uplift across the study area. Locally as much as 10m of relief can be observed in the beach rock terraces that trend from sea level in the southwest to over 10m in the northeast segment. Differential local and regional uplift coupled with sea level variability have influenced coastal geology and morphology in the study area, and obtaining quantitative results has proved problematic.

FOSSILIZED DINOSAUR BONE

If fossilization was simply replacement of bone with stone, fossil and living bones wouldn't be as chemically similar as they are, and the intricate details found in fossilized dinosaur bones would not have survived. Even more intriguing is the fact that some of the proteins in bone have survived the fossilization process, in dinosaurs and "older" fossils, a fact very consistent with a young earth.

Fossilization is essentially a process of denaturing bone, similar to the denaturing of animal skin in leather manufacturing. The mineral that makes the live bone hard, apatite, combines with fluorine (in groundwater) to form fluorapatite. The living tissue in bone (mostly proteins such as collagen) largely decay away, and the resulting void spaces get filled with mostly quartz minerals.

Fossilization takes place when the following steps, which nicely fit a young-earth flood-geology context, occur.

I. Rapid burial to prevent immediate disintegration.

II. Rapid fluoridation and quartzification to spare the bone from bacterial decay and percolating fluids while buried in the sediment. Depending on the mineral content of the groundwater ("the fountains of the great deep" which "burst forth," [Gen. 7:11]) this could have occurred very rapidly. Experiments on buried shrimp show that even soft tissue can be preserved in a matter of weeks under the right conditions.

III. Survival of the bone through chemical change over time ("eons" of survival required, of course, for evolutionists and long-age creationists).

Dinosaur Bone makes awesome jewelry, stunning yellows, reds, and browns, with black.

GARNETS

Garnet actually is a group of minerals with the same crystalline structures which comes in a wide variety of colors. The different varieties are detailed below.

Pyrope Garnet: One of the most common varieties (pictured above), it is red in color, often with a brownish tint to it. It has been found in in Burma, Madagascar, China, Sri Lanka, South Africa, Tanzania and the United States.

Rhodolite Garnet: Purplish red or rose-colored garnet.

Almandite Garnet: Named based on the town it was found in, this stone is red with a violet tint. Mined from deposits in India, Brazil, Madagascar and in the United States.

Spessartine Garnet: Also called Spessartite. Named from the word for "forest" where they were found in Germany. It's color is orange to red-brown. Also found in Burma, Brazil, Kenya, China, Sri Lanka, Madagascar, Tanzania and the United States.

Tsavorite Garnet: Green to emerald green in color. The best specimens are clear and are often faceted in emerald cuts. Found in Tanzania and Kenya.

GASPEITE

Gaspeite was discovered in 1966 in the Lemieux Township of the Gaspe’ Peninsula, Quebec, Canada. It is also found in western Australia – the best from North of Perth, Australia. It is found as a secondary mineral around nickel sulfide deposits. Gaspeite comes in light green to an unmistakable apple green color. Gaspiete is usually cut into cabochons. A light, almost apple green color is quite unique and some varieties are almost a neon green. It may contain tan to brownish patches of matrix which gives it a distinctive character. This stone is named for the location of the original discovery in Gaspe Peninsula, Quebec, Canada where material was found that was NOT suitable for the jewelry industry. We only have one source for this treasured stone and he tells us that the last discovery of "cuttable" material (meaning hard enough and of good quality for use in jewelry & beads) was in 1990 in Weegemoogha, Australia. This discovery was a 40 ton block of Gaspeite, with only 27 tons of cuttable material, so YES the availability of this stone will eventually run out to the jewelry industry. It is considered both RARE and collectable. Gaspeite has a hardness of 5.

Chemistry: (Ni, Mg, Fe)CO3, Nickel Magnesium Iron Carbonate
Class: Carbonate
Group: Calcite

Gaspeite is found as a secondary mineral around nickel sulfide deposits. It was thought of as just a gangue mineral by miners when it was encountered and usually placed in the mines dumps or tailings. A gangue mineral is a mineral that probably contains the ore metal, but its chemistry is such that processing it is either impossible or unprofitable. Such was the case with gaspeite despite being rich in nickel. Of course lapidary craftsmen have a different view of gaspeite's profitability! Gaspeite is named for its type locality of Gaspe' Peninsula, Lemieux Township, Gaspe'-ouest County, Quebec, Canada, but the best material of late is coming from North of Perth, Australia.

PHYSICAL CHARACTERISTICS:
Color is a pale green to apple green.
Luster is vitreous to dull.
Transparency: Crystals are usually translucent, massive material is opaque.
Crystal System is trigonal; bar 3 2/m.
Crystal Habits include rhombohedrons and scalenohedrons, but crystals are very rare. More commonly found massive.
Cleavage is perfect in 3 directions forming rhombohedrons.
Fracture is uneven.
Hardness is 4.5 - 5.
Specific Gravity is 3.7 (somewhat heavy for a translucent mineral).
Streak is yellowish green.
Other Characteristics: Effervesces slightly in hydrochloric acid.
Associated Minerals include millerite, pentlandite, skutterudite, annabergite and other nickel minerals.
Notable Occurrences include the type locality of Gaspe' Peninsula, Lemieux Township, Gaspe'-ouest County, Quebec and Sudbury, Ontario, Canada and a new source of carvable material from Kambalda and Widgie Mooltha which is North of Perth, Australia.
Best Field Indicators are color, locality, reaction to acids, cleavage and density.

HEMATITE

Known in some countries as "bloodstone" because of the color it changes the cooling water of saw blades when it's cut, it often resembles metal when polished. The sample above is a Specular Hematite variety with shining specks. When pieces are sliced thin enough, they appear red and transparent. Deposits are found in Bangladesh, England, Brazil, China, Czech Republic, New Zealand and the state of Minnesota in the U.S.A.

HEMIMORPHITE

Chemistry: Zn4 Si2 O7 (OH)2 -H2O, Hydrated Zinc Silicate Hydroxide.
Class: Silicates
Subclass: Sorosilicates
Uses: minor ore of zinc
Specimens
Hemimorphite is one of the more common sorosilicates. Its most noteworthy characteristic is its polar or hemimorphic crystals from where it gets its name. The crystal structure produces a different termination at each end of the crystal. One termination, the "bottom" is rather blunt being dominated by a pedion face while the opposite end, the "top" is terminated by the point of a pyramid. The crystal structure contains tetrahedrons of ZnO3 OH, interlocked with Si2 O7 groups and water molecules. The zinc is at the center of the tetrahedron while the three oxygens, along with an OH group, are at the four points of the tetrahedron. These tetrahedrons are all aligned in the same direction with one face parallel to the pedion termination and the "top" of the tetrahedrons pointing toward the pyramidal termination.
Hemimorphite was originally named calamine but this name had been used for another mineral and hemimorphite was proposed and is now in wide spread use. The hemi means half while the morph means shape and thus hemimorphite is aptly named. Only a few other minerals show hemimorphic character such as tourmaline, but none show it as well as hemimorphite. Clusters of hemimorphite that show well shaped crystals do not always show the hemimorphic character. Because the crystals of a single specimen tend to grow outward with either the "top" or the "bottom" as the overall orientation for that specimen. In order to see the hemimorphic character either a doubly terminated specimen is necessary or two different clusters with different orientations will be needed.

Specimens of hemimorphite tend to be of two very different forms (seems like a trend with this mineral). One form produces very glassy, clear or white, thin, bladed crystals, often well formed showing many crystal faces. Many times these crystals are arranged in fan shaped aggregates. The other form produces a blue to blue-green botryoidal crust that resembles smithsonite or prehnite. Prehnite has a lower density and is usually greener and has different associations with other minerals. Smithsonite has a shimering luster that causes a play of light across the rounded surfaces and has a higher density that hemimorphite. Often hemimorphite will show rough crystal ridges or "cock's comb" structures over top of the basic botryoidal crust. For a collector both forms are a must in their mineral collections.

HONEYCOMB CALCITE

Honeycomb Calcite is a beautiful and impressive form of calcite mined exclusively in the state of Utah. Much like onyx and marble it can provide a colorful replacement or a dramatic accent stone for architectural & artistic applications. The name comes from the remarkable honeycomb appearance when viewing a polished surface. It is formed by the growth of long fibrous tubular cells and crystals of honey color outlined by white membranes surrounding each cell. The Coloring is attributed to iron deposits at the time of formation.

HOWLITE

Howlite is a white colored stone usually with black matrix. Howlite is often presented in it's dyed form, as shown above. Sometimes used to imitate turquoise, it's natural black or brown veining lends itself well to this. Naturally occurring in snow white coloring, which in this form it is often passed off as white turquoise or "white buffalo".

IOLITE

Iolite is normally violet-blue in color, albeit, a sometimes dull blue. The best quality faceted gems can sometimes resemble tanzanite or sapphires. Prior to the 1980s, it was not readily available, but supply has increased, making it a beautiful addition to most jewelry.

It's name is derived from the Greek word for violet. Sometimes misleadingly called a "Water Sapphire" because it looks clear and watery from the side, but can resemble a sapphire when looking at it head on.

Iolite was used by the Vikings on cloudy days as a sort of compass. They were able to locate the position of the sun by looking through thin, clear slices of it. It has properties that acted like a light polarizer and canceled out the mist and haze in the atmosphere.

Deposits are found in Sri Lanka, India, Brazil, Burma, Madagascar, Tanzania and the United States

JADE

There have been some civilizations in the South Pacific, Asia and Central America where Jade has been more prized than Diamonds or Gold. It is a very beautiful, yet tough stone that is resistant to chipping and breakage. The ancient Chinese philosopher Confucius said it was valuable because it represented the whole of purity, sureness of intelligence, music and loyalty due to it's characteristics. Today it is worn by many Asians for good luck and health.

The name "Jade" came from the Spanish conquistadors who named it according to the job that native Mexicans were using it for. As it was thought by them to relieve kidney ailments, the Spanish named it "piedra de ijada" which meant "stone of the loins." Eventually the Spanish term evolved into "Jade." The early Roman civilization also considered it to be a good treatment for kidney ailments such as nephritis (kidney inflammation) leading to it being named "lapis nephriticus" for "stone of nephrite." The Latin term was subsequently reduced to "nephrite" and is sometimes used as an alternate name of Jade.

A French chemist, Augustine Damour, noted in 1863 that jade was two different minerals. She used the word "Jadeite" for Burmese jade to distinguish it from the Chinese jade "nephrite." The Chinese had know of the difference between the two since the early seventeen hundreds.

Jadeite and Nephrite are both comprised of tightly interlocking crystals, which is different from the single crystals that comprise most other gems.

Jadeite is a little bit harder and denser and can take more time to polish. It is comprised of crystals which tend to be somewhat more granular and coarse.

Nephrite is most common and typically found in olive or forest green. The oldest known sources come from China. It is slightly stronger since it's crystal components are more intergrown than Jadeite.

VARIETY INFORMATION:
VARIETY OF: both jadeite and nephrite
USES: Gemstone and ornamental stone.
COLOR: shades of emerald green as well as white, gray, yellow, orange and violet.
INDEX OF REFRACTION: is approximately 1.66 (jadeite) and 1.62 (nephrite)
HARDNESS: 6.5 - 7
CLEAVAGE: does not apply due to massive nature of jade
CRYSTAL SYSTEM: monoclinic
SPECIMENS

JASPER

A member of the Chalcedony species, Jasper comes in many different varieties. It's is derived from the Greek word which means "spotted stone." This dense, finely grained stone, can contain up to 20 percent foreign materials which actually determines it's color streak and appearance for categorization.

Jasper is found worldwide and comes in colors like red, brown, yellow, gray and green. Black and Blue are the most rare colors found. It comes in many varieties, Agate, Banded, Basanite, Egyptian, Hornstone, Leopard Skin, Moukaite, Picture, Plasma, Scenic, & Zebra Jasper.

JET

Jet is Anthracite Coal which is a sedimentary rock formed from plants that lived millions of years ago. Jet is used a great deal in contemporary and traditional Native American inlay jewelry.

KYANITE

It's name is derived from the Greek word for blue. It can often have inclusions and streaks. Having a variable hardness makes it quite difficult to cut.

Mined from Brazil, Burma, Kenya, Austria, Zimbabwe, Switzerland and the United States.

LABRADORITE

Named after the peninsula in Canada where it was originally found, it's a member of the Feldspar group. Specifically, plagioclase feldspar. It has a luminescent quality, similar to a moonstone, but with more of a streaked design of blues and greens. Some specimens show a more complete rainbow spectrum as well. This quality is best seen when the stone is in just the right direction in relation to the light source because of the distortion created by the microscopic exsoluction lamellae of high and low calcium plagioclase phases.

Deposits are obtained from Canada, Madagascar, Australia, Russia, Mexico and the United States.

LAPIS LAZULI

Lapis has been highly prized since ancient Babylonian and Egyptian times. Genuine lapis is a natural blue, opaque stone. It is brilliant deep blue and sometimes possesses small sparkling gold or silver colored flecks which are pyrite inclusions. The best lapis comes from Afghanistan and Argentina. It can also be found in Russia, Chile, Canada and occasionally the U.S.

LION'S PAW SHELL

Lion's Paw Shell simular to Spiny Oyster comes from Baja Mexico. The interior of the shell has less white and these shells can be orange on one side with purple on the inside thus they make wonderful beads purple and orange, as well as cabochons.

MALACHITE

Malachite is named for the Greek word “mallow” which is a green herb. Malachite is a copper ore that comes in a brilliant green marked with bands of contrasting shades of the same green. Malachite is often found in copper producing areas such as Russia, Mexico, Australia, England, Southwest US and notably Zaire is a major producer today. Never clean malachite with any product containing ammonia.

MOTHER OF PEARL

Mother of Pearl is a hard, iridescent inner layer of certain shells such as abalone, pearl oyster and mussel. Mother of pearl varies in shades of white, yellow, pink and gray. Care should be taken not to expose it to chemicals.

MOONSTONE

Moonstones come in a variety of colors, ranging from colorless to white, gray, brown, yellow, orange, green, or pink. Clarity ranges from transparent to translucent.

Description: (K, Na) AlSi3O8, Moonstone (also called rainbow moonstone) is soft milky white stone, the most valuable variety of feldspar with an rainbow sheen. Moonstone shows a silvery or bluish iridescence, that is caused by the intergrowth of two different types of feldspar with different efractive indexes. The term moonstone also has been applied to the plagioclase feldspars peristerite and labradorite, which also exhibit iridescence.

The name's origin: The moonstone named for its semblance in color to the moon.

Moonstone was very popular with the Romans, who thought it was formed out of moonlight, also used in Roman jewelry since 100 AD. In India moonstone is considered a sacred stone to this day.

MUSCOVITE QUARTZITE

Art Smith, Mineralogist-Geologist wrote: I did a microscopic examination of the bead material that you call Muscovite. It is a natural stone, probably a metamorphic rock called quartzite. It is composed of well-fused grains of clear to slightly cloudy quartz with interspearsed flakes of pale tan, slightly iron stained, mica that is probably muscovite. The iron staining seems to be most concentrated on the edge of the muscovite flakes and so emphasizes them when the stone is polished. This is an excellent hard and durable stone that will make good beads, cabochons or other lapidary items.

OPAL

Opal is a paradoxical gemstone, and one of the most fascinating.
It is a form of quartz, but is not a form of quartz. Quartz is very common, yet has many rare and precious gem varieties. Opal itself has numerous varieties. It is the most colourful gemstone, but some forms are colourless. It can be very bright and beautiful, and it can be dull and dead. It is best known for its flashes of colour, but some varieties have no flashes of colour, and are still opals. It can be black, and it can be white. Its best known attribute, the brilliant flashes of many colours, are not called opalescence, but irridescence. Some people think opal is unlucky, but it is one of the most valuable and desirable of gems. Actually because opal is a gel, it is, strictly speaking, not a form of quartz. Quartz is a crystalline form of silicon dioxide, opal is a solid gel. However because the chemical formula is the same except that opal is hydrous, that is it contains some water which is chemically attached to the silicon dioxide molecules. Opals were known and mined in Roman times. The Roman mines were in and around Cervenica, previously in Czechoslovakia, although we have now lost track of all the recent changes in Balkan geography. Now most the opal the market is from Australia or Mexico. Austrailian opal is the finest.

PEARLS

Color: The color of pearls varies with the mollusk and its environment. It ranges from black to white, with the rose of Indian pearls esteemed most. Other colors are cream, gray, blue, yellow, lavender, green, and mauve. All occur in delicate shades.
Cultured pearls are being produced in virtually every color of the rainbow.

Description: The chief component of the nacre that constitutes the pearl is aragonite CaCO.
Pearls are formed by a mollusk consisting of the same material (called nacre, or mother-of-pearl) as the mollusk's shell. It is a highly valued gemstone.
The shell-secreting cells of the mollusk are located in the mantleof its body. When a foreign particle penetrates the mantle, the cells attach to the particle and build up more or less concentric layers of pearl around it. Irregularly shaped pearls called baroque pearls are those that have grown in muscular tissue. Pearls that grow adjacent to the shell are often flat on one side and are called blister pearls.
Pearls are characterized by their translucence and lustre and by a delicate play of surface color called orient. The more perfect its shape (spherical or droplike) and the deeper its lustre, the greater its value. Only those pearls produced by mollusks whose shells are lined with mother-of-pearl (e.g., certain species of both saltwater oysters and freshwater clams) are really fine pearls. Pearls from other mollusks are reddish or whitish, porcellaneous, or lacking in pearly lustre.
The surface of a pearl is rough to the touch. Pearls come in a wide range of sizes. Those weighing less than 1/4 grain (1 pearl grain = 50 milligrams = 1/4 carat) are called seed pearls. The largest naturally occurring pearls are the baroque pearls; one such pearl is known to have weighed 1,860 grains.
Cultured pearl is natural but cultivated pearl produced by a mollusk after the intentional introduction of a foreign object inside the creature's shell.

The discovery that pearls could be cultivated in freshwater mussels is said to have been made in 13th-century China, and the Chinese have been adept for hundreds of years at cultivating pearls by opening the mussel's shell and inserting into it small pellets of mud or tiny bosses of wood, bone, or metal and returning the mussel to its bed for about three years to await the maturation of a pearl formation. Cultured pearls of China have been almost exclusively blister pearls.
The production of whole cultured pearls was perfected by the Japanese. The research that led to the establishment of the industry was started in the 1890s by Mikimoto Kokichi, who, after long experimentation, concluded that a very small mother-of-pearl bead introduced into the mollusk's tissue was the most successful stimulant to pearl production. Cultured pearls closely approximate natural pearls.
The finest Oriental pearls are found in the Persian Gulf. Other notable sources of fine-quality pearls include the Gulf of Mannar between India and Sri Lanka, the waters off Celebes, Indonesia, and the islands of the South Pacific. In the Americas, the Gulf of California, the Gulf of Mexico, and the waters of the Pacific coast of Mexico have yielded dark-hued pearls with a metallic sheen as well as white pearls of good quality.
Freshwater mussels in the temperate zone of the Northern Hemisphere have produced pearls of great value, as for example those from the Mississippi River. Pearling is a carefully fostered industry in central Europe, and the forest streams of Bavaria, in particular, are the source of choice pearls. Freshwater pearling in China has been known from before 1000 BC.
Cultured pearls: Northern Australia established its first cultured pearl farms in the 1960s, that by the mid-1970s were an established industry, producing pearl shell as well as pearls. Japan and Australia are the largest producers of cultured pearls, though Fiji also produces some.

PEITERSITE

Coming soon

PERIDOT

Peridot (pronounced pair-a-doe) is the gem variety of olivine. Olivine, which is actually not an official mineral, is composed of two minerals: fayalite and forsterite. Fayalite is the iron rich member with a pure formula of Fe2SiO4. Forsterite is the magnesium rich member with a pure formula of Mg2SiO4. Olivine's formula is written as (Mg, Fe)2SiO4 to show the substitution of the magnesium and iron. Peridot is usually closer to forsterite than fayalite in composition although iron is the coloring agent for peridot. The best colored peridot has an iron percentage of less than 15% and includes nickel and chromium as trace elements that may also contribute to the best peridot color.
Gem quality peridot comes from the ancient source of Zagbargad (Zebirget) Island in the Red Sea off the coast of Egypt; Mogok, Myanmar (formerly known as Burma); Kohistan, Pakistan; Minas Gerais, Brazil; Eifel, Germany; Chihuahua, Mexico; Ethiopia; Australia; Peridot Mesa, San Carlos Apache Reservation, Gila County, Arizona and Salt Lake Crater, Oahu, Hawaii, USA. The best quality peridot has historically come either from Myanmar or Egypt. But new sources in Pakistan are challenging that claim with some exceptional specimens. The Arizona gem material is of lesser quality, but is far more abundant and is therefore much more affordable. An estimated 80 - 95% of all world production of peridot comes from Arizona. The Myanmar, Pakistani and Egyptian gems are rarer and of better quality and thus quite valuable approaching the per carat values of top gemstones. Possibly the most unusual peridot is that which comes from iron-nickel meteorites called pallasites. Some are actually facetted and set in jewelry.

Peridot is perhaps derived from the French word peritot which means unclear, probably due to the inclusions and cloudy nature of large stones. It could also be named from the Arabic word faridat which means gem. In either case, peridot has been mined as a gemstone for an estimated four thousand years or better, and is mentioned in the Bible under the Hebrew name of pitdah. Peridot gems along with other gems were probably used in the fabled Breastplates of the Jewish High Priest, artifacts that have never been found. The Greeks and Romans referred to peridot as topazion and topazius respectively and this name was later given to topaz, to end the confusion with the two gems. Historical legend has it that peridot was the favorite gemstone of Cleopatra. Pliny wrote about the green stone from Zagbargad Island in 1500 B.C.. Even until recently have jewelers used the term "chrysolite" (latin for golden stone) in referring to peridot gems for some reason. This term has also been used to refer to other gemstones, of a more golden color.

Zagbargad (Zebirget) Island has been known as St John's Island and was mined for centuries. Before World War I, this island was extensively mined and produced millions of dollars worth of gems. Since then the mining has been off and on and at present is all but nonexistent. Still, specimens from here are available at times and it certainly is a classic mineral locality.

Throughout time, peridot has been confused with many other gemstones, even emerald. Many "emeralds" of royal treasures have turned out to be peridots! And although peridot is distinctly a different shade of green, many jewelers refer to peridot as "evening emerald". Emerald is a dark green as opposed to a yellow green and always contains inclusions. Other green gemstones confused with peridot include apatite (which is much softer); green garnets (have no double refraction), green tourmaline and green sinhalite (both of which are strongly pleochroic), moldavites (no double refraction) and green zircon (significantly heavier). All of these gemstones rarely have as nice a yellow component to their green color as does most peridot, but darker green peridot can be confusing when good crystal form is not discernible.

Peridot is a beautiful gemstone in its own right and is widely popular. Its popularity is said to be increasing yearly and with new finds in Pakistan producing exceptionally well crystallized specimens, peridot can be fun to collect for years to come.

PETRIFIED WOOD

Petrified wood consists of a wide variety of minerals including silica, silicates, carbonates, sulfates, sulfides, oxides, and phosphates. They all can permineralize wood to form petrified wood (Adams 1920). However, petrified wood most commonly consists of silica (Si02) in the form of either opal or chert (Stein 1982).

Silicified wood is usually found within one of two types of strata. First, it occurs within accumulations of volcanic ash, tuff, and breccia, e.g. the petrified forests of Yellowstone National Park. Second, silicified wood also occurs within sands, silts, and muds deposited by rivers and streams that have hardened to sandstones, siltstones, and shale. Typically, the sandstones, siltstones, and shales that contain silicified wood also contain redeposited tuffaceous materials or volcanic ash. The silicified wood found in Petrified Forest National Park in Arizona and the Miocene strata of Louisiana and Texas occur within such strata (Knauth 1972:44).

Origin of Petrified Wood
Silicified wood forms in these deposits, because of the presence of dissolved silica within the groundwater. The silica is derived from the dissolution of the volcanic material by the groundwater within the volcanics or sediments. This dissolved silica in the form of monomeric silicic acid attaches itself to the lignin and cellulose of the wood. With time, a layer of the monomeric silicic acid forms on the exposed woody tissues. The monomeric silicic acid dehydrates into silica gel. Additional layers of the monomeric silicic acid attach to this silica gel eventually filling and encasing the wood with silica gel. A rapid loss of water converts the silica gel into amorphous silica (opal) (Leo and Barghoorn 1976; Scurfield and Segnit 1984).

Within 10 to 40 million years, the opal of the silicified wood further dehydrates and crystallizes into microcrystalline quartz (chert). Factors such as temperature and pressure may speed or slow the process, but eventually the opal of the silicified wood becomes chert (Stein 1982). During the change from opal to chert in silicified wood, the relict woody texture may either be retained or lost.

During the silicification process, various materials and minerals may be incorporated into the silica gel. For example, manganese dioxides, iron oxides, organic matter and authegenic clay can alone or in combination color the opal or chert that forms silicified wood. Because each piece of wood becomes silicified in its own local geochemical environment, the trace and major materials and elements that it contains will vary greatly from piece to piece even within the same stratum (Knauth 1972:45; 1981). Therefore, trace element analysis is generally useless in tracing the source of any silicified wood.

Types Of Petrified Woods
Within the Tertiary strata that outcrop in southeast to southwest Texas and into Louisiana, three types of silicified wood can be recognized. They are rather nondescript silicified wood, palm wood, and a massive silicified wood. The nondescript silicified wood consists of silicified wood that possesses a recognizable woody structure. The relict woody structure is fine and nondescript. It is not identifiable without oriented thin sections, specialized references, and comparative material (Blackwell et al. 1983:2). Therefore, this type is best described just as "silicified wood".

The second type of silicified wood is commonly called including the State Fossil "petrified palm wood" by geologists and rock collectors. Palm wood is a group of fossil woods that contain prominent rod-like structures within the regular grain of the silicified wood. Depending upon the angle at which they are cut by fracture, these rod-like structures show up as spots, tapering rods, or continuous lines. The rod-like structures are sclerenchyma bundles that comprise part of the woody tissues that gave vertical strength to the Oligocene and Miocene tree genera, Palmoxylon (Blackwell et al. 1983:4-5).

The third type of silicified wood is massive silicified wood. The silicification of the wood or subsequent transformation of silica gel to opal or chert has obliterated any trace of the grain of the former wood. The destruction of the structure of the silicified wood has resulted in a massive opal or chert that lacks any visible indication of its origin. Because of its variable, massive nature and heterogeneous trace element composition, many investigators, e.g. Jolly (1982) and Jolly and Kerr (1984), have often failed to recognize the nature of this material. The Eagle Hill Chert found within West-Central Louisiana is a local, massive silicified wood (Heinrich 1984). A similar massive silicified wood called "golden palm" occurs in equivalent strata within East-Central Texas (Patterson 1985).

PICASSO MARBLE

A gorgeous stone native to southeastern Utah. Utah Picasso Marble is a common building stone, it is a classic sculptors stone. Some marbles are famous such as Italian white and Belgian black marble. The colors vary and may be found in pinks, yellows, and browns. Marble is a soft rock and yet dense in structure. It was once limestone in the Precambrian era. The sedimentary limestone masses were sometimes contacted by hot magnas and the pressure altered the limestone. Other minerals from the magna then infiltrated the limestone causing feathery lines and beautiful designs such as Picasso Marble found in Beaver County, Utah. The scenic effect and color contrast in black and gold has made this marble a popular cutting rock for the lapidarest.

RAINBOW CALSILICA

is a newly-found, multi-colored, layered stone composed of calcium and silica from a mine in Chihuahua, Mexico. This stone has been recently used for Zuni fetish carvings and in Native Indian jewelry. I am not too sure of the reality of this stone, I have heard rumors that it is just colored sand layered and treated like they treat turquoise.

RHODOCHROSITE

Rhodochrosite (whose name means rose-colored) is a very attractive mineral with an absolutely one-of-a-kind, beautiful color. Although it can be an ore of manganese, it is its ornamental and display specimen qualities that make it a very popular mineral. The color of a single crystal can just astound the observer with its vivid pink-rose color that seems to be transmitted out of the crystal as if lit from within.
Individual crystals are found in well shaped rhombohedrons and more rarely scalahedrons. In a massive form its pink and white bands are extremely attractive and are often used in semi-precious jewelry. Rhodochrosite is often carved into figurines and tubular stalactitic forms are sliced into circles with concentric bands that are truly unique in the mineral kingdom. Fine crystals are sometimes cut into gemstones, but rhodochrosite's softness and brittleness limit it as a gemstone for everyday use.

Identification of rhodochrosite is fairly easy despite a few similarly colored minerals such as rhodonite. Rhodonite is harder and has different cleavage; but perhaps the best distinguishing factor is its lack of reaction to acids. Rhodochrosite will easily with show some reaction to cold acids which demonstrates its carbonate chemistry. Basically, any rose-pink carbonate is considered rhodochrosite; however some calcites with a small amount of manganese impurities can be pink in color. The manganese replaces some of the calciums in calcite but a complete series between calcite and rhodochrosite is not established. Differentiating pink calcite from rhodochrosite may require a fluorescence test as rhodochrosite is distinctly non-fluorescent and manganese is a fluorescent activator in calcite.

There are many localities for rhodochrosite that are of great reknown. Beyond a doubt, the best locality for rhodochrosite is the Sweet Home Mine in Colorado. It is unmatched for its superb rhodochrosite crystals that exhibit the best features of the species; a fine bright rose color and sharp well formed crystals. Some specimens from here are quite large and of world class distinction.

Other localities have produced some fine specimens as well. Catamarca, Argentina has an old inca silver mine that has produced fine stalatitic examples of rhodochrosite that are unique and very attractive. Cut cross-sections reveal concentric bands of light and dark rose colored layers. These specimens are carved and used for many ornamental purposes.

Mont Saint-Hilaire, Quebec, Canada has produced many fine rare minerals but it also produces some nice rhodochrosite specimens as well. Specimens from here are generally small, but have a good color and are associated with rarer minerals.

There are many Peruvian rhodochrosite localities that have produced a number of good specimens. These crystals are usually paler in color than other specimens, but are accented by interesting metal sulfide minerals.

N'Chwanging Mine, Hotazel, South Africa has produced possibly the best examples of scalahedral crystals of rhodochrosite. The unusual crystal habit is due in part to this being one of a few sedimentary crystallizing environments for the species. Most other localities are the result of metamorphism, late stage igneous intrusion or more commonly hydrothermal precipitation.

RHODONITE

Chemistry: (Mn, Fe, Mg, Ca)5(SiO3)5 , Manganese Iron Magnesium Calcium Silicate.
Class: Silicates
Subclass: Inosilicates
Group: Pyroxenoid
Uses: ornamental and semi-precious stone and as a minor ore of manganese
Specimens
Rhodonite is an attractive mineral that is often carved and used in jewelry. It is named after the Greek word for rose, rhodon. Its rose-pink color is distinctive and can only be confused with rhodochrosite and the rare mineral, pyroxmangite, MnSiO3. Rhodochrosite however is streaked with white minerals such as calcite and is reactive to acids. While rhodonite does not react to acids and is usually associated with black manganese minerals and pyrite. Pyroxmangite is a little harder to distinguish because the two minerals are closely related and x-ray studies are usually needed when found massive. Crystals of pyroxmangite are often twinned as is not the case with rhodochrosite crystals. Crystals of rhodonite, while not in nearly the same abundance as massive rhodonite, are still found and distributed on the mineral markets. They come from a few notable localities and are considered classics by collectors.

RUBY

Ruby is the red variety of corundum, the second hardest natural mineral known to mankind. The non-red variety of corundum is Sapphire Sapphires are well known among the general public as being blue, but can be nearly any color. The red color in ruby is caused by trace amounts of the element chromium. The best shade of red for ruby is often given the name "pigeon blood red", but ruby can be any shade of red up to almost pink.

Oriented rutile crystal inclusions cause a six-rayed-star light effect (called asterism) to form the popular Star Ruby.

Rubies come from all over the world but good gemstones are found at Thailand, India, Madagascar, Zimbabwe, North Carolina in the U.S., Afghanistan, Pakistan, Sri Lanka, Kenya, Tanzania, Kampuchea, and perhaps most notably, Burma.

Rubies have a famous place in science - the first lasers were made from artificial ruby crystals. They still are used for this purpose although other materials offer improved efficiency. Some ruby crystals show the fluorescence (actually very short term phosphorescence) that makes a laser possible.

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