Feature Gems & Gemology, Winter 2010, Volume 46, No. 4

Yellow Scapolite from Ihosy, Madagascar

Margherita Superchi, Federico Pezzotta, Elena Gambini, and Emanuela Castaman

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Attractive yellow to light greenish yellow gem scapolites have been mined from a skarn deposit near the town of Ihosy, in southern Madagascar, since the late 1990s. Chemical analysis indicates that the scapolites have a mostly meionite content, with lesser amounts of marialite and a small percentage of silvialite. These results are agreeable with the RI measurements and IR spectra. Inclusions were identified as diopside, garnet (andradite-grossular), and mica (probably phlogopite) consistent with the minerals accompanying scapolite in Ihosy skarns. The samples’ UV fluorescence appears to be distinctive from that of commercially available scapolites from other localities.