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Dumortierite in quartz * Jadeite with high albite content * Moldavite imitation * Iridescent scapolite * Composite quartz beads * CVD synthetic diamond with unstable color * The Foldscope.
The Ambatofinandrahana region is most famous for quartz with and without inclusions, epitactic hematite on rutile, bastnasite, tourmaline and beryl, including huge crystals of aquamarine, with
dumortierite crystals, encased in solid pegmatite.
(Saul subsequently discovered the ruby deposits in the Tsavo West area of Kenya--at what became the famous John Saul Ruby mine.) Saul bought some of de Souza's crystals, at that time labeled as
dumortierite, and sent them to a number of people for a proper identification.
Dumortierite [Al.sub.7](B[O.sub.3])(Si[O.sub.4])[O.sub.3]
Associated minerals are: alkali-feldspar, plagioclase, quartz, sekaninaite, andalusite, topaz, garnet, biotite, muscovite,
dumortierite, schorl, zircon, apatite, monazite, ilmenite, pyrite, cordierite, sericite and chlorite.