Gem Wealth of Tanzania

Abstract

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Pink to Pinkish Orange Malaya Garnets from Bekily, Madagascar

“…Based on our observations and photographs in the literature (see, e.g., Manson, 1982, 1985;Rouse, 1986;Arem 1987;Dirlam et al 1992), most malaya garnets from East Africa are intense orange, pinkish orange, or yellowish orange. Malaya garnet from Bekily also is pinkish orange, but the orange to yellowish orange material is uncommon.…”

Rubies and Sapphires from Winza, Central Tanzania

“…With the exception of some remarkable stones primarily from the Morogoro deposits, Tanzania was historically known to produce mostly cabochonquality rubies or stones that required heat treatment (Dirlam et al, 1992). Therefore, the recent discovery of high-quality rubies at Winza is a welcome event for the Tanzanian gem trade.…”

Sapphire and Garnet from Kalalani, Tanga Province, Tanzania

“…The garnet group at Umba is represented by pink-purple rhodolite, "malaia" garnet (called also "Umbalite"), color-change garnet, and pale pink grossular. Cr-tourmaline, spinel, scapolite, apatite, zircon, Cr-diopside, kyanite, and turquoise have also been reported from the Umba area (Dirlam et al, 1992). The second author recently identified a mineral new to Umba, gemmy brown enstatite.…”

“…The history of the Kalalani area is closely associated with the nearby Umba River area, which has been described by Solesbury (1967), Dirlam et al (1992), and Keller (1992). Although there are no official data on gem production from the Kalalani area, the senior author estimates that to date, the total production of fancy-color sapphire from the area is about 400 kg.…”