Cushion-cut painite, 0.30-ct, 3.8 x 3.4 mm, very dark brownish red, Myanmar. © The Gem Trader. Used with permission.
Until 2001, only three painite crystals were known to exist. Since then, additional discoveries have produced many more specimens of this deep red gemstone, but facetable material remains very rare.
| Data | Value |
|---|---|
| Name | Painite |
| Crystallography | Hexagonal, pseudo-orthorhombic. |
| Refractive Index | 1.787-1.816 |
| Colors | Dark red, garnet-like in hue; brownish red-orange. |
| Hardness | 8 |
| Fracture | Conchoidal. |
| Birefringence | 0.029 |
| Cleavage | Not determined. |
| Luminescence | Weak red in LW, greenish or strong red in SW. |
| Luminescence Present | Yes |
| Luminescence Type | Fluorescent, UV-Long, UV-Short |
| Absorption Spectrum | Faint Cr spectrum. |
| Formula | Ca4Al20BSiO38. |
| Pleochroism | o = deep ruby red; e = pale brownish orange. |
| Optics | o = 1.816; e = 1.787. Uniaxial (-). |
| Optic Sign | Uniaxial - |
| Etymology | After the discoverer, gemologist A. C. D. Pain. |
| Occurrence | Gem gravels. |
| Inclusions | Minute cavities in thin sheets; inclusions of tabular hexagonal crystals (phlogopite). |
| Luster | Vitreous. |
| Specific Gravity | 4.0-4.3 |
| Transparency | Transparent. |
These photos show both the transparency and very dark colors of a gem-quality painite crystal. 0.7 x 0.3 x 0.2 cm, Ongaing, near Mogok, Myanmar. © Rob Lavinsky, www.iRocks.com. Used with permission.
Painites are found only in Myanmar. The first painite specimen, a single crystal, was identified as a new gem species in 1957. Until 2001, only two more crystals were found. Since then, more painites have been discovered. Over a thousand crystals and fragments have now been recovered, but most of this material isn’t facetable.
This cut corner square painite shows deep red/brownish orange pleochroism. 0.75 cts, Myanmar, 2005 find. Photo by Allyce Kosnar. © Kosnar Gem Co. Used with permission.
Although painites have a hardness of 8, great brilliance, and attractive red colors, they present some challenges for gem cutters. Even gem-quality rough is typically highly included and fractured. As a result, faceters tend to cut these gems small and shallow, which can impair their brilliance.
Although new finds of painite have produced very heavily included and fractured rough, an expert gem cutter can still bring out the beauty of this rare material. Very dark brown, rectangle step-cut painite and rough. The faceted gem weighs 0.75 cts and measures 3.7 x 6.8 mm. © The Gem Trader. Used with permission.
Painites have colors and a specific gravity that overlap with those of almandines, spessartites, and rubies. This means that some cut gems might have been misidentified as rubies or garnets. However, painites have refractive index values that differ from rubies, and their birefringence and absorption spectrum should distinguish them from garnets.
In 2007, a brown specimen from the Natural History Museum, London, originally identified as a tourmaline with rubies from Mogok, proved to be a painite.
A deep red, glassy painite crystal surrounded by dozens of rubies. Discovered between 2000 and 2003. The painite measures 2.2 cm long; specimen 4.0 x 3.5 x 3.0 cm, Kyauk-Pyat-Thet, Mogok, Myanmar. © Rob Lavinsky, www.iRocks.com. Used with permission.
No known synthetics.
No known gem treatments.
Myanmar remains the sole source of painites. In addition to Ongaing, the type locality, Kyauk-Pyat-Thet in Mogok and Namyazeik in Kachin State have produced gem-quality material.
The first two discovered painite specimens, weighing 1.7 and 2.118 grams, respectively, now reside in the Natural History Museum, London.
Although painites do have great resistance to scratching, they may also contain inclusions and fractures that make them susceptible to impacts from everyday wear or heat and vibrations from mechanical cleaning systems. Consult with a gemologist to evaluate your gemstone and determine the best way to set and clean such a rare piece. Otherwise, a soft brush, mild detergent, and warm water should pose no risks for painites. For more care recommendations, consult our gemstone jewelry cleaning guide.
Oval-cut painite, 0.90 cts, Myanmar, 2005 find. Photo by Allyce Kosnar. © Kosnar Gem Co. Used with permission.
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