In January 1967, a Tanzanian prospector named Jumanne Mhero Ngoma found traces of a blue-violet crystal in the Merelani Hills, in the shadow of Mount Kilimanjaro. A separate account, more widely told outside Tanzania, credits a Goan tailor and prospector, Manuel de Souza, with the same discovery several months later, in July 1967, after he reportedly mistook the blue fragments for another stone. Both accounts remain in circulation, and neither is definitively settled, so we hold them as two threads of the same origin rather than a single fact.
What both versions agree on is the rarity of place. To date, every piece of tanzanite in commercial circulation has come from a single stretch of the Merelani Hills, roughly seven kilometres long: the only known commercial source on Earth. In 1968, Tiffany & Co. named the stone after the country where it was found, choosing "tanzanite" over the more clinical "blue zoisite," and introduced it to an international audience.
Newly mined, the rough is rarely blue. Much of it emerges from the ground brownish, and it is gentle, controlled heating, a standard and disclosed practice across the trade, that reveals the violet-blue colour the stone is known for. Tanzanite is not born in its final colour. It is uncovered.
