Achalaite ((Fe2+, Mn)(Ti, Fe3+, Ta)(Nb, Ta)2O8) is a black mineral of the wodginite group, first discovered in 2013.
It crystallizes in the monoclinic system and has a dark, metallic luster, a specific gravity of 6.285 and a Mohs hardness of 5.5.
Achalaite occurs in the intermediate zone of topaz- and tantalite-bearing pegmatite. Associated minerals include rutile, quartz and albite.
Its name comes from the type locality: the Achala batholith in Córdoba, Argentina and the mineral has been approved by the IMA with the acronym 2013-103.
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