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Magnesioaxinite - Sold


Magnesioaxinite is a magnesium calcium aluminum borate-silicate. The mineral name denotes its magnesium content while recalling the long established iron-dominant axinite described by René Haüy in his 1801 Traité de Minéralogie. The name axinite alludes to its axe-like crystal shape. Magnesioaxinite was the first new species recognized in the tanzanite mines, originally described from a cut gem by Jobbins et al. (1975) in the Journal of Gemmology (whole issue PDF). The International Mineralogical Association has applied a hyphenated nomenclature to the axinite species, dubbing this species axinite-(Mg) (Burke, 2008).

A transparent blue crystal, free of matrix. Like well known gem zoisite from this locality, i.e. tanzanite, the blue color of magnesioaxinite comes from minor vanadium substitution. This example shows chipping along its edges, presumably from local recovery methods. 9.61 cts.