gems, corundum, Tanzania.12, spinel, tanzanite, zoisite, Merelani, Mahenge, Tunduru

In September 2024, the authors visited some of the major gem-producing districts in Tanzania and Madagascar (see map, Figure 1). In Tanzania, the itinerary included Merelani (tanzanite), Kalalani (garnet) and Umba Valley (sapphire and Mahenge spinel; see map, Figure 2). The journey then continued in Madagascar (described in Part 2, to be published in the December 2026 issue of The Australian Gemmologist) to Ambondromifehy (sapphire), Sahatany Valley (tourmaline) and Ilakaka (sapphire).