Duftite is a scarce, lead copper hydroxy-arsenate mineral, PbCuAsO4(OH). It has a nonmetallic, dull to glassy luster and is heavy for its size, the result of its lead & copper content. Some duftite samples have significant calcium and zinc content as well, substituting for the lead and copper, respectively. Duftite's color is various shades of green, but has a white to pale green streak. It forms tabular to blocky crystals, microcrystalline crusts, and botryoidal crusts. Other duftite physical properties include a hardness of 4.5, no obvious cleavage, uneven to conchoidal fracture, and transparent to translucent crystals.
Duftite is a secondary mineral, formed by oxidation of lead- and copper-bearing sulfide deposits.
Duftite from the Tsumeb Mine, Tsumeb, Namibia.