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News Archive
New Pegmatite Gems from Tsarafara, Madagascar
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Figure 1. This green spodumene crystal from Tsarafara measures 7 cm long. Photo by F. Danet.
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Spodumene, tourmaline, and morganite were recently recovered as well-formed crystals and gem rough from a pegmatite mine at Tsarafara, near Mount Ibity in the Sahatany Valley of central Madagascar. The gems came from two pockets that were found in September 2006. The mine has been worked by local miners, using hand methods, in shafts reaching up to 20 m deep. This contributor visited the mine three times in October 2006 to document the production. Tsarafara is also known as Ankadilava or Ambalaroy in the gemological literature.
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Figure 2. Tourmaline crystals from Tsarafara have been cut into colorful slices (here, 1–4 cm in diameter). Photo by F. Danet.
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The spodumene ranged from colorless to pale green (e.g., figure 1), pale blue, and pink (rarely, bicolored blue-pink). At least 150 kg were produced, in translucent to eye-clean crystals up to 50 cm long. The largest crystal reportedly measured about 80 cm long. Most of the spodumene was exported as mineral specimens for collectors and as rough for Asian lapidaries; only a few cut stones have been seen in Madagascar.
Hundreds of tourmaline crystals were produced, commonly with a black “skin” and concentric internal layers of violet pink, dark green, grayish green to bluish green, brownish yellow, and/or colorless. Although some of the tourmaline has been faceted into multicolored gems (grayish green, dark green, and violet) weighing up to 30 ct, a significant amount of the material has been cut into attractive slices that typically measure 1–8 cm in diameter (e.g., figure 2). Most of the rough, which was of low quality and recovered in small sizes, was sold to African traders for the Asian market to make carvings and beads.
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Figure 3. The best-quality morganite from Tsarafara is notable for its transparency and orangy pink color. The crystal shown here is 4 cm in diameter. Photo by F. Danet.
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The Tsarafara pegmatite also yielded a few kilograms of morganite, most of which was a pale yellowish orange. The best morganites were eye-clean orangy pink crystals (e.g., figure 3) that measured up to 10 cm in diameter. In December 2006, this contributor saw a clean, 66 gram yellowish orange piece of rough that would probably yield an approximately 100 ct faceted stone. Most of the well-formed crystals have been retained as specimens for collectors. By the end of 2006, almost all the deep workings had collapsed due to flooding during the rainy season. The miners therefore shifted to higher ground in the southern part of the mine, where they found narrow, elongate crystals of multicolored tourmaline (brown, grayish green, violet, and pink). The terminations of some of the crystals contained abundant hollow tubes that created chatoyancy when cut into cabochons.
Fabrice Danet
Style Gems, Antrisabe, Madagascar
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