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The Gemstones
Dioptase
Consumer Information
What color is it?: A beautiful emerald green.
What is the story behind this gemstone?: Dioptase is a rather unusual gemstone that will rarely be found in your basic jewelry stores. It is a beautiful gemstone with a very unusual combination of green colors.
Can I wear it everyday?: Well, not really. It is rather soft (5) and is sort of brittle. So it is best worn in pendants and earrings. But for those purposes it will wear well every day.
Is it expensive?: It can be. A nice dioptase will cost about the same as a very nice chrome tourmaline.
Is it a birthstone?: No.
What do I need to know before going shopping?: Be prepared to shop around...and wait. Few jewelry stores will carry dioptase in their normal inventory. However, if you have a good independent retail jeweler with an experienced gemologist on staff you should have no trouble finding some of these very special gemstones to choose from.
General Information
Source: Russia, United States, Chile, others
Chemical: Cu6(Si6O18)6H2O a hydrous silicate of copper found in conjunction with copper ore deposits
Formation: Generally in connection with hydrothermal hollows and cavities where copper ore is oxidizing.
Crystal System: Trigonal
Unusual Properties: Beautiful green color is classic formation.
Gemological Information
RI: 1.644 - 1.709
Birefringence: .065 + -
Optic Character: U +
Specific Gravity: 3.30 + -
Hardness: 5
Transparency: TP
Special Identifying Properties and Tests: None
Synthetics: No.
Imitations: Many possible.