Mottramite

Mottramite was the first species I ever encountered from Tsumeb and so remains one of my favourite minerals from this world-famous mine. This small miniature is interesting alone for its high density, a property readily appreciated as soon as it is handled. The specimen is composed entirely of Mottramite, an anhydrous vanadate hydroxide forming coliform mounds and fronds, rising vertically from a flat base. Characteristic of certain habits of Mottramite at Tsumeb, undulating folds ripple across the mounds, delineating individual Mottramite crystals. The overall colour is of darkish forest green with a rusty speckled dusting, and from the opposite direction, a preferential layer of much brighter, limey-pistachio green highlights this delightful specimen. I should add that the Tsumeb mine is in Namibia, but suspect everyone reading this already knows!