Authentic Smoky Bisbee Blue Turquoise Cabochon. ( 16 cts, backed, N ) This Turquoise is from Bisbee, Arizona. The Bisbee Mine was closed to Turquoise Mining in approximately 1976. Bisbee is highly coveted and collected worldwide and has become very scarce. Our authentic Bisbee Turquoise is a great investment for Jewelers and individuals as well. It is known to be one of the finest types of Turquoise on Earth.