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Cafarsite


Cafarsite is a complex calcium iron titanium arsenite. While originally thought to contain water, separate crystal structure determinations by Gatta et al. (2018) and Cametti et al. (2018) both show cafarsite to be anhydrous; additionally, both studies found minor but essential fluorine. Graeser (1966) states that mineral name indicates it chemical composition, apparently with some poetic license.

This specimen consists of two intergrown cafarsite crystals, each measuring 1.1 cm across. The crystals have an icosahedral habit, possessing 20 faces when complete, which results from the combination of a pyritohedron (having 12 faces) with an octahedron (having 8 faces). The main crystal is perhaps 60% complete, and the secondary crystal less so, both showing contact where they separated from matrix. Separation from matrix is typical of freeze and thaw conditions of the Alps. Material collected by Toni Imhof. Many examples of cafarsite have chemically altered and show poor luster; Imhof's pocket had exceptional luster for the species.

Price: $100

Item code: MS1596

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