A rib of massive, to extremely well-crystallized, Braunite with a few intergrown Calcite crystals forms the basis of this excellent miniature specimen of this uncommon manganese silicate species. Compared to other 'ores' of manganese, Braunite is rarely seen in distinct, visible crystals, making the discovery at N'Chwaning mines in South Africa exceptional and the world's best. The Braunite forms excellent 3-dimensional 'chunky', tabular, glossy, black crystals (to 9 mm across and 5 mm wide) with small (to 4 mm), greyish-white, rounded scalenohedral Calcite crystals sparsely interspersed. The largest crystal is missing part of its back edge, but there are many other really great freestanding crystals, showing excellent crystal faces all round. This is very fine demonstration of the perfect tetragonal form which Braunite crystals take on the rare occasions that they are able to.
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