If you are Tsumeb fan and like the unusual, then this specimen from the Weyand collection is worth a second look. On first impressions the glossy black Goethite coating looks like mineral pitch, or tar, drizzled across the surface of the specimen. This is, in turn, encrusted with jewel-like gemmy colourless elongated Calcite crystals. Combined, this makes for an interesting and unusual Tsumeb piece, but turn the specimen around and things get weirder. The matrix is, in fact, a slightly layered ball-shaped nodule with an off-centre hollow core. The 'nodule' is generally beige coloured internally and is probably a dolomitized limestone, but the hollow core is lined with contrasting murky-green glossy microcrystals of what is most likely Duftite. Duftite also coats the external edges of the nodule, but very thinly, and is subsequently covered in the tar-like black layer of Goethite which encapsulates the whole outer surface prior to the deposition of Calcite crystals on one half of the half-dome. A couple of the Calcite crystals show abrasion to their tips, but this requires detailed inspection. Overall, the specimen displays very well and presents a really unusual combination.
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