Description
Black Onyx Gemstone 7.08ct
Description
This Black Onyx is Natural Gemstone Which is Black Colour, it’s Originates from India and it’s exact Weight is 7.08ct the Measurements are 13.90×10.00×6.20mm. The Shape and Cut of This Stone is Oval Cabochon It’s Graded Translucent and Clarity is Good. This 7.08ct Black Natural Onyx Gem is available for ready to Ship anywhere in The World. You Can also Select Certification and Shipment Method as Optional.
Details
| Summary No | AK00650 |
| Species | Natural Black Onyx |
| Weight | 7.08ct |
| Shape/cut | Oval Cabochon |
| Colour | Black |
| Dimension | 13.90×10.00×6.20mm |
| Clarity | Good |
| Transparency | Translucent |
| Origin | India |
| Treatment | None |
Black Onyx Gemstone 7.08ct
Properties Of Onyx
Chemical Composition: Sio2
Hardness: 7
Specific Gravity (Density): 2.61Â
Refractive Index: 1.53 – 1.54Â
About: Black Onyx
Onyx belongs to chalcedony quartz and is a granular microcrystalline. Chalcedony is used by gemologists as a species name for all cryptocrystalline quartzes(E.G., Agate, Chrysoprase, Bloodstone, Jasper, Carnelian, Moss agate, Onyx and Sard as well as specifically only the bluish-white-gray variety). Although the crystal quartzes (rock crystal, amethyst, etc.)have a vitreous luster, chalcedonies are, in their natural state, waxy or dull. Records show the chalcedony have been stained by the ancient roman and ancient Egyptians. The usual method is the sugar-acid treatment. Chalcedony is dipped in a sugar solution which penetrates the porous rock, following cracks and flaws within the piece and the lines of the banding. The chalcedony is then heated in sulphuric acid, which carbonises the sugar, darkening it and turning it black. Deposits are found in Brazil, India, Madagascar, Malawi, Namibia, Zimbabwe, Sri Lanka, Uruguay, and California.
