Usambara Iolite Mines
📍 Tanga, Tanzania · -4.9000°, 38.4000°
The 1990s Usambara discovery yielded violet iolite crystals to 100 carats — Tanzanian material shows cleaner saturation than Indian alluvials and anchors modern supply.
📍 Tanga, Tanzania · -4.9000°, 38.4000°
The 1990s Usambara discovery yielded violet iolite crystals to 100 carats — Tanzanian material shows cleaner saturation than Indian alluvials and anchors modern supply.