Quartz with Siderophyllite 1.95 ct
Cushion Cut 8.70 x 7.0  mm
Tanzania
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Quartzite with siderophyllite

Trade name is also “Cherry Tanzurine”. In fact is quartzite with this type of mica; the material is generally milky with many fractures and is used for beads ,cabochons and tumbled; only a very small percentage of it is of gem quality. Siderophyllite is a rare member of the mica group of silicate minerals with formula Kfe2+2Al(Al2Si2)O10(F,OH)2.

It comes from Malambo,west of Lake NatronAfrican Rift Valley,Arusha Region Tanzania.