Painite

Painite, once believed to be the rarest mineral on earth, is today still considered very rare. It was first found in Myanmar by British mineralogist and gem dealer Arthur C.D. Pain in the 1950s. When it was confirmed as a new mineral species, the mineral was named after him.For many years, only three small painite crystals were known to exist. Before 2005 there were fewer than 25 known crystals found, though more material has been unearthed recently in Myanmar.The chemical makeup of painite contains calcium, zirconium, boron, aluminium and oxygen (CaZrBAl9O18). The mineral also contains trace amounts of chromium and vanadium. Painite has an orange-red to brownish-red color similar to topaz due to trace amounts of iron. The crystals are naturally hexagonal in shape, and, until late 2004, only two had been cut into faceted gemstones.
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General Information:
 Chemical Formula:
CaZrBAl9O18
 Composition:
(Molecular Weight = 672.94 gm)
Calcium 5.96 % Ca
Zirconium 13.56 % Zr
Aluminum 36.09 % Al
Boron 1.61 % B 
Oxygen 42.80 % O 
 Empirical Formula:
CaZrBAl9O18
Physical Properties:
 Color:
brownish, brownish red, orange red, or red.
 Density:
4.03
 Diaphaniety:
Transparent
 Hardness:
8 - Topaz
 Luster:
Vitreous (Glassy)
 Streak:
white
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