6. Painite – $9,000 per gram
Painite is a thought to be the rarest gem mineral.
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.
At $9,000 per gram Painite is the 6th most expensive substance to be found on Earth’s surface!
