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Johachidolite - Sold

Johachidolite is a calcium aluminum borate mineral. The mineral name follows from its discovery in the Jōhachidō District (now Sangpal-tong) of North Korea (Iwase & Saito, 1942). Crystal structure solution by Moore & Araki (1972) simplified the ideal formula to CaAlB3O7, which led Aristarain & Erd (1977) to formally redefine the species with approval from the International Mineralogical Association.

Amongst a parcel of Burmese gems examined in 1998, an exotic yellow 14 carat stone turned out be johachidolite. This Burmese stone represented a second world occurrence of the species! The geological setting remained a mystery until later finds in 2005-2007 brought further material to light. Peretti et al., (2007) studied hundreds of stones and matrix pieces and visited the occurrence. Most johachidolite occurs as incomplete crystals in orthoclase and sodalite matrix with phlogopite.

Johachidolite here forms a two crude crystals in orthoclase matrix, with minor phlogopite and fluorapatite. The larger johachidolite crystal is 21 by 9 mm and shows a 10 by 8 mm face with color zoning from colorless to orange. The other crystal is 8 by 4 mm and shows a good orange color. Matrix pieces are rather rare, most having been broken down for gem rough.