Painite - $9000 / Gram

Painite is a very, very, rare crystal, which belongs to boron family. It was first discovered by a British scientist named Arthur Pain in 1950s. This mineral is so rare that you can find less than twenty five Painite crystals in the world. Painite is so rare that you can't even find one now to buy, even after you are ready to shell out $9000 a gram! 

This Post Belongs To 15 Most Rare and Expensive Materials In The World