Kyanite 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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Kyanite Gemstones by Size
This table shows distribution of Kyanite 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:1.54 cts
Heaviest:8.76 cts
Average:4.59 cts
Total photos:14
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| General Information | ||||||||||||
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| Other Names/Trade Names: | ||||||||||||
| Chemical Formula |
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| Kyanite Treatments | ||||||||||||
| Pale blue kyanite (also known as cyanite or disthene) is reported to lose its color on heating to 1200°C (Smith et al, 1978) - Nassau (1984) | ||||||||||||
| Physical Properties of Kyanite | ||||||||||||
| Mohs Hardness | 4 to 7.5, Blue Chart Gem Identification (2010) Low hardness parallel to crystal lengthMore from other references | |||||||||||
| Specific Gravity | 3.55 to 3.70, Blue Chart Gem Identification (2010) More from other references | |||||||||||
| Cleavage Quality | Perfect, Gemmological Tables (2004) More from other references | |||||||||||
| Fracture | Splintery, Gemstones (2009) | |||||||||||
| Optical Properties of Kyanite | ||||||||||||
| Refractive Index | 1.710 to 1.735, Blue Chart Gem Identification (2010) More from other references | |||||||||||
| Optical Character | Biaxial/+,-, Blue Chart Gem Identification (2010) More from other references | |||||||||||
| Birefringence | 0.017 to 0.021, Gemmological Tables (2004) More from other references | |||||||||||
| Pleochroism | Distinct: light-blue, light green -- blue, green -- dark blue, dark green, Gemmological Tables (2004) More from other references | |||||||||||
| Dispersion | 0.020, Gemstones (2009) | |||||||||||
| Chatoyancy | Asteriated (4), Gemmological Tables (2004) More from other references | |||||||||||
| Colour | ||||||||||||
| Colour (General) | Blue, blue-green, green, brown, yellow, red, colourless, Gemmological Tables (2004) More from other references | |||||||||||
| Causes of Colour | Blue, Fe2+-O-Ti4+ charge transfer, Fe2+-O-Fe3+ charge transfer, Fe2+ and Fe3+ in octahedral coordination can all be involved, with contribution from Cr3+ in octahedral coordination. Green, V3+ in octahedral coordination; Fe3+ in octahedral coordination. Orange, Mn3+. Color change, Cr3+ in octahedral coordination, Pragmatic Spectroscopy For Gemologists (2011) | |||||||||||
| Transparency | Transparent,Translucent, Gemstones (2009) | |||||||||||
| Lustre | Pearly, Gems, Sixth Edition (2006) More from other references | |||||||||||
| Fluorescence & other light emissions | ||||||||||||
| Fluorescence (Long-Wave UV) | Blue: usually reddish, Blue Chart Gem Identification (2010) More from other references | |||||||||||
| Crystallography of Kyanite | ||||||||||||
| Crystal System | Triclinic, Blue Chart Gem Identification (2010) More from other references | |||||||||||
| Habit | Often fibrous, Blue Chart Gem Identification (2010) More from other references | |||||||||||
| Geological Environment | ||||||||||||
| Where found: | Kyanite occurs in gneisses and schists and in granite pegmatites., Gems, Sixth Edition (2006) | |||||||||||
| Spectrographic Data | ||||||||||||
| Calculated Spectra: Click spectra for more information | Kyanite - Locality: Unknown | |||||||||||
| Further Information | ||||||||||||
| Mineral information: | Kyanite information at mindat.org | |||||||||||
| Significant Gem Localities | ||||||||||||
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