Oligoclase
Kenya
2.57 carats
© Rarestone.com
The name oligoclase derived from the Greek "oligos" - little, and "clasein" - to break, because the mineral was thought to have a less perfect cleavage than albite. This name was given by August Breithaupt in 1826.
Oligoclase 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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Oligoclase Gemstones by Size
This table shows distribution of Oligoclase 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:0.74 cts
Heaviest:8.95 cts
Average:2.90 cts
Total photos:21
Do you have a larger Oligoclase? Why not upload a photo?
| General Information | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| A variety or type of: | Feldspar | |||||||||
| Chemical Formula |
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| Oligoclase Treatments | ||||||||||
| Irradiation may turn colourless material blue if lead and water impurities are present (see amazonite). Oligoclase has also been reported to turn orange and green upon irradiation. | ||||||||||
| Physical Properties of Oligoclase | ||||||||||
| Mohs Hardness | 6 to 6.5, Gemmological Tables (2004) More from other references | |||||||||
| Specific Gravity | 2.62 to 2.67, Gemstones of the world (2001) More from other references | |||||||||
| Cleavage Quality | Perfect,Good, Gems, Sixth Edition (2006) Perfect in one and good in another direction | |||||||||
| Fracture | Conchoidal, Gems, Sixth Edition (2006) | |||||||||
| Refractive Index | 1.538 to 1.550, Gemmological Tables (2004) More from other references | |||||||||
| Optical Character | Biaxial/-, Gemmological Tables (2004) More from other references | |||||||||
| Birefringence | 0.010, Gemmological Tables (2004) More from other references | |||||||||
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