FluorapatiteFluorapatite
L-R 3.20, 2.72, 4.60, 3.59 ct. The specimens on the left are untreated, those on the right are heated to 600º C. Madagascar. GIA collection (L-R #20856, 29202, 29203, 33785); Mark Mauthner photo.
Copyright: mmauthner