Search the Web with our sponsor, Overture. Hyacinth has a hardness of 7.5 and a specific gravity of 4.65. Hyacinth is mined in Sri Lanka. Even more confusing is the origin of the name, which comes from the Greek hyakinthos, which refers to blue gemstone. JADE Jade is a semi-precious stone that ranges in color from green to white to lilac to brown to almost black.
Translucent jade is more highly valued than opaque jade.
The Chinese have prized jade for thousands of years and regarded it as having medicinal properties when worn or ingested as a powder. Japanned finish in jewelry is when metal is finished with a lustrous, black lacquer. Jasper has been used for intaglio carvings. Jasper is a type of quartz belonging to the chalcedony family. It is often sealed with petroleum products.