Hematoid Quartz and Mottramite

Quartz (see previous entries)

Mottramite

Mottramite, very similar to descloizite, forms pyramidal crystals, tabular or prismatic and, in other cases, crusts and compact masses with fibrous structures and botryoidal surfaces. The colour varies from orange-red to brownish black, but it can also be green in tone.

It is affected by acids and is easily soluble. It forms in the oxidation zones of lead, zinc and copper.

The most common use of these minerals relates to the extraction of vanadium.