Herderite
Brazil
4.07 carats
© Rarestone.com
Herderite forms good single crystals, twinning is common. Gem material is transparent and has a range of colours, including yellow, blue, pink, violet and green, some crystals are colourless.
Clear crystals are faceted into attractive gems.
Herderite 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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Herderite Gemstones by Size
This table shows distribution of Herderite 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:0.29 cts
Heaviest:5.43 cts
Average:1.72 cts
Total photos:17
Do you have a larger Herderite? Why not upload a photo?
| General Information | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Chemical Formula |
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| Physical Properties of Herderite | |||||||||
| Mohs Hardness | 5 to 5.5, Blue Chart Gem Identification (2010) More from other references | ||||||||
| Specific Gravity | 2.90 to 3.02, Blue Chart Gem Identification (2010) More from other references | ||||||||
| Cleavage Quality | Indistinct, Gemstones (2009) | ||||||||
| Fracture | Sub-Conchoidal, Gemstones (2009) | ||||||||
| Optical Properties of Herderite | |||||||||
| Refractive Index | 1.587 to 1.642, Blue Chart Gem Identification (2010) More from other references | ||||||||
| Optical Character | Biaxial/+,-, Blue Chart Gem Identification (2010) More from other references | ||||||||
| Birefringence | 0.028 to 0.032, Blue Chart Gem Identification (2010) More from other references | ||||||||
| Dispersion | Nil, Gemstones (2009) | ||||||||
| Colour | |||||||||
| Colour (General) | Greyish blue, colourless, pale green, yellowish., Gemstones of the world (2001) More from other references | ||||||||
| Transparency | Transparent,Translucent, Gemstones of the world (2001) More from other references | ||||||||
| Lustre | Vitreous, Gemstones of the world (2001) More from other references | ||||||||
| Fluorescence & other light emissions | |||||||||
| Fluorescence (General) | Commonly greenish to violet, Blue Chart Gem Identification (2010) More from other references | ||||||||
| Fluorescence (Short Wave UV) | Some specimens exhibit moderate green fluorescence, Gemstones (2009) | ||||||||
| Fluorescence (Long-Wave UV) | Some specimens fluoresce deep-blue or moderate green., Gemstones (2009) | ||||||||
| Phosphorescence | Some specimens are reported to have shown persistent phosphorescence, Gems, Sixth Edition (2006) | ||||||||
| Crystallography of Herderite | |||||||||
| Crystal System | Monoclinic, Blue Chart Gem Identification (2010) More from other references | ||||||||
| Habit | Pseudo-orthorhombic crystals, Gems, Sixth Edition (2006) More from other references | ||||||||
| Geological Environment | |||||||||
| Where found: | Is believed to occur in complex granite pegmatites, Gems, Sixth Edition (2006) | ||||||||
| Further Information | |||||||||
| Mineral information: | Herderite information at mindat.org | ||||||||
| Significant Gem Localities | |||||||||
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