Olmiite Lustrous Thumbnail Specimen

Highly Lustrous Thumbnail Sized Olmiite Specimen

Small but highly lustrous Olmiite from N’chwaning II, Kalahari Manganese Field, Northern Cape, South Africa.

Size: 27mm  x 19mm

Weight: 10.5 grams

Olmiite is a relatively new mineral, only being officially named as a new species by the IMA in 2006. To date, it is found only in the Kalahari Manganese Field of South Africa. It is unusual for a newly discovered mineral to form is such large and excellent examples, with many well-formed and highly aesthetic examples of this mineral.  It forms in radiating spheres, as botryoidal, acicular, and wheat sheaf crystal groups, in groups of ball-shaped aggregates, and in stacked crystal plates. Individual pyramidal crystals are uncommon.

Olmiite forms a solid solution series with the much rarer mineral Poldervaartite. Many specimens that had been labelled as Poldervaartite have in fact been Olmiite upon analysis. Olmiite is named after Filippo Olmi, an Italian mineralogist from Florence, Italy.