Class : Oxides and hydroxides
    Subclass : Arsenites
    Crystal system : Triclinic
    Chemistry : PbFe₄As₁₀O₂₂
    Rarity : Very rare

Ludlockite is an extremely rare complex oxide of arsenic, iron and lead. It is a secondary mineral known in the oxidation zones of polymetallic deposits as well as in the slag of lead ores. It was named in honor of two American mineral collectors and dealers from New Jersey, Frederick Ludlow Smith and Charle Locke Key, who discovered the mineral in Tsumeb (Namibia). Ludlockite is generally fibrous and forms under the microscope elongated lamellae united in divergent sheaves, more rarely prismatic crystals with a square section, 4 cm in maximum length, of an orange-brown to brownish red color.

Main photo : Ludlockite from Tsumeb, Oshikoto, Namibia © Elmar Lackner

Lamellar twins on {0-11} are common.

No fakes recorded for this mineral species.