Glossary
Tanzania
Tanzania offers an extraordinary variety: sapphire, ruby, alexandrite and even pink diamonds. Since 1994 the Tunduru region in the south has produced world-class sapphires; in the Umba valley in the north, sapphires are found in many colours.
Ruby and alexandrite
Rubies come from Winza and Longido, where they also occur embedded in green zoisite. Alexandrites with a distinct colour change have been found at Lake Manyara.
Origin
Sapphires from Tunduru often look almost identical to stones from Sri Lanka, Myanmar and Madagascar and are rarely reported with a Tanzanian origin. The Williamson mine occasionally yields pink diamonds.
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Updated 2026-10-06