Chrome-Tourmaline
Tanzania
5.75 carats
© Palagems
It can be used as a lower-priced alternative to tsavorite garnet and emerald.
The main sources of the material are Kenya and Tanzania, but some fine chrome tourmalines are found in Myanmar.
Chrome-Tourmaline Gemstones by Colour
This table shows the variety of hues this gemstone can be found in. Click on a photo for more information.
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Chrome-Tourmaline Gemstones by Size
This table shows distribution of Chrome-Tourmaline gemstone sizes that are listed on this site. This can give a good indication as to the general availability of this gemstone in different sizes.
Contributed photos
Lightest:0.25 cts
Heaviest:5.75 cts
Average:0.90 cts
Total photos:18
Do you have a larger Chrome-Tourmaline? Why not upload a photo?
| General Information | |||||||
|---|---|---|---|---|---|---|---|
| A variety or type of: | Tourmaline | ||||||
| Physical Properties of Chrome-Tourmaline | |||||||
| Mohs Hardness | 7 to 7.5, Blue Chart Gem Identification (2010) | ||||||
| Specific Gravity | 2.85 to 3.35, Blue Chart Gem Identification (2010) | ||||||
| Tenacity | Brittle, Gems, Sixth Edition (2006) | ||||||
| Optical Properties of Chrome-Tourmaline | |||||||
| Refractive Index | 1.614 to 1.666, Blue Chart Gem Identification (2010) | ||||||
| Optical Character | Uniaxial/-, Blue Chart Gem Identification (2010) | ||||||
| Birefringence | 0.014 to 0.040, Blue Chart Gem Identification (2010) | ||||||
| Pleochroism | Strong: dark green - yellow-green, Gemstones of the world (2001) | ||||||
| Colour | |||||||
| Colour (General) | Fine emerald color, Blue Chart Gem Identification (2010) Possible green to (dark)-red color change | ||||||
| Colour (Chelsea Filter) | Reddish, Blue Chart Gem Identification (2010) | ||||||
| Causes of Colour | Green due to chromium and/or vanadium., The Gemstone Book (2012) More from other references | ||||||
| Transparency | Transparent,Translucent,Opaque, Gemmological Tables (2004) | ||||||
| Lustre | Vitreous, Gemstones (2009) | ||||||
| Fluorescence & other light emissions | |||||||
| Fluorescence (General) | Weak to none, Gemstones of the world (2001) | ||||||
| Crystallography of Chrome-Tourmaline | |||||||
| Crystal System | Trigonal, Blue Chart Gem Identification (2010) | ||||||
| Habit | Long crystals with triangular cross section and rounded sides, definite striation parallel to main axis, Gemstones of the world (2001) | ||||||
| Further Information | |||||||
| Mineral information: | Chrome-Tourmaline information at mindat.org | ||||||
| Significant Gem Localities | |||||||
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