Tanzanite, a blue-violet variety of the mineral zoisite, has only ever been found in commercial quantities in a roughly two-square-kilometer area near the Merelani Hills at the foot of Mount Kilimanjaro, since its discovery in 1967. This makes it one of the rarest gemstones in the world, limited to a single small deposit.
Record no. MRB-2026-005984
Tanzanite - A Gemstone Found Nowhere Else on Earth
Reference Record – Not Certified
This record is compiled from publicly available sources for reference. It has not been examined or certified by The Book of World Records.