Common. First, second, and third oxidation zones.
- 1st Oxidation Zone
- 2nd Oxidation Zone
- 3rd Oxidation Zone
Paragenetic and General Notes
Recognised very early in Tsumeb's history (Maucher, 1908), mottramite occurred extensively in the upper portions of both the first and second oxidation zones (Keller, 1977). Typically as radially-structured masses, sometimes dendritic, or as moss-like coatings; single crystals of acicular habit are rare.
Readily confused with duftite.
Mottramite is reported to form pseudomorphs after the following minerals: calcite (rare), tennantite (rare), wulfenite (rare).