Ludlockite Locality: Tsumeb , Otjikoto (Oshikoto) Region, Namibia ( Locality at mindat.org ) Size: miniature, 3.9 x 2.3 x 1.5 cm Ludlockite Ludlockite, found here at its type locality, is a strange iron-lead arsenite that was found around 1970 in the very lower depths of the Tsumeb Mine, in its deepest oxidation zone filled with all kinds of bizarre mineralogy. The color of ludlockite is interesting, but when combined with the metallic lustre to its fibrous crystals, the overall effect of a ludlockite specimen is unique and visually stunning. It looks like hair dipped in bronze and gelatin. This is a very rich, sturdy cluster of intergrown acicular crystals, perched on a minimal amount of ore matrix. A rare, display-sized, beautiful miniature specimen for this species normally available to collectors today only as micros or small pockets rather than with such large freestanding clusters such as this. Ex. Robert Whitmore Collection. — Photo: Robert M. Lavinsky · CC BY-SA 3.0
Ludlockite
Ludlockite is an IMA-recognized mineral species in the oxides & hydroxide class, with the chemical formula PbFe³⁺₄As³⁺₁₀O₂₂.
It crystallizes in the triclinic crystal system (space group A-1).
Key properties: Mohs hardness 1.5–2; specific gravity 4.33–4.4; Pale brown streak; Subadamantine luster; optically biaxial.
IMA symbol Ldl, IMA status: approved, named in 1969.
Found in sulfide ore from a complex polymetallic hydrothermal ore deposit (Tsumeb, Namibia).
It is found associated with Zincian siderite, tennantite, chalcocite, pyrite, bornite, germanite, quartz; leiteite, reniérite, stolzite, schneiderhöhnite (Tsumeb, Namibia).
The name refers to Fredrick LUDlow Smith III, (1939–) and Charles LOCKe Key (1935–), American mineral dealers then resident in New Jersey, USA, who supplied the first specimens for study.