
India
6.86 carats
© gemselect.com
| General Information | |||||||||||||||||||||
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| A variety or type of: | Chalcedony, which is a variety of Quartz | ||||||||||||||||||||
| Chemical Formula |
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| Chrysoprase Treatments | |||||||||||||||||||||
| Dyed green (chromium) - chelsea: pinkish to reddish. Might be dyed with nickel-rich solution: standard tests limited - Blue Chart Gem Identification, Herve Nicolas Lazzarelli, 2010, p 7 | |||||||||||||||||||||
| Chrysoprase Simulants | |||||||||||||||||||||
| Grayish chalcedony is soaked in mixture of water, acid, chromium or nickel compounds, then heated and dryed. This will create a material with green to bluish green colour. - GIA 2019 | |||||||||||||||||||||
| Physical Properties of Chrysoprase | |||||||||||||||||||||
| Mohs Hardness | 6.5 to 7, Blue Chart Gem Identification (2010) | ||||||||||||||||||||
| Specific Gravity | 2.58 to 2.64, Gemstones of the world (2001) More from other references | ||||||||||||||||||||
| Tenacity | Brittle, Gemstones of the world (2001) | ||||||||||||||||||||
| Cleavage Quality | None, Gemstones of the world (2001) | ||||||||||||||||||||
| Optical Properties of Chrysoprase | |||||||||||||||||||||
| Refractive Index | 1.530 to 1.543, Blue Chart Gem Identification (2010) | ||||||||||||||||||||
| Optical Character | Uniaxial/+, Gemmological Tables (2004) | ||||||||||||||||||||
| Birefringence | up to to 0.004, Gemstones of the world (2001) | ||||||||||||||||||||
| Pleochroism | Absent, Gemstones of the world (2001) | ||||||||||||||||||||
| Dispersion | None, Gemstones of the world (2001) | ||||||||||||||||||||
| Colour | |||||||||||||||||||||
| Colour (General) | Colored by nickel: (yellowish)-green, Blue Chart Gem Identification (2010) More from other references | ||||||||||||||||||||
| Colour (Chelsea Filter) | Greenish, Blue Chart Gem Identification (2010) | ||||||||||||||||||||
| Causes of Colour | Green colour is caused by microscopic inclusions of silicates with Ni-bearing layers (willemseite, népouite, etc)., Management Team (2012) More from other references | ||||||||||||||||||||
| Transparency | Translucent,Opaque, Gemmological Tables (2004) More from other references | ||||||||||||||||||||
| Fluorescence & other light emissions | |||||||||||||||||||||
| Fluorescence (General) | None, Gemstones of the world (2001) | ||||||||||||||||||||
| Crystallography of Chrysoprase | |||||||||||||||||||||
| Crystal System | Trigonal, Gemmological Tables (2004) | ||||||||||||||||||||
| Habit | Microcrystalline aggregates, Gemstones of the world (2001) | ||||||||||||||||||||
| Geological Environment | |||||||||||||||||||||
| Where found: | It occurs in quartz veins in nickel-bearing rocks or in veins in laterites overlying Ni-bearing serpentinites (Queensland) and associated with jadeite in veins in serpentinized gabbro and ultramafic inclusions (Lower Silesia.), Gems, Sixth Edition (2006) | ||||||||||||||||||||
| Spectrographic Data | |||||||||||||||||||||
| Calculated Spectra: Click spectra for more information | |||||||||||||||||||||
| Further Information | |||||||||||||||||||||
| Mineral information: | Chrysoprase information at mindat.org | ||||||||||||||||||||
| Significant Gem Localities | |||||||||||||||||||||
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