Alabandite, a sulphide of manganese, is a very rare species worldwide and crystals were always considered exceptionally rare. In recent years two localities have upped the standard: Uchucchacua mine in Peru; and Merelani Hills in Tanzania. Both have produced exceptional crystals, but in quite different forms. Those from Uchucchacua mine are much more octahedral in shape and often display spinel-twinning. This miniature specimen from Uchucchacua mine displays particularly well-developed crystals of Alabandite forming an intergrown group of lustrous metallic dark grey colour, with twinning very apparent on one crystal, which reaches 2.5 cm across. The crystals sit upon a contrasting pale crystalline Rhodochrosite matrix.
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