The world's rarest gem is believed to be painite, a gem that most have never even heard of. Rarity does not equate to beauty in gems, however. The painite is an orangey or reddish brown, with the brown tint coming from iron in the crystal.

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.