Class : Sulfides and sulfosalts
    Subclass : Sulfides
    Crystal system : Tetragonal
    Chemistry : Cu₃AsS₄
    Rarity : Rare to uncommon

Luzonite is a rare copper-arsenic sulfide found in low- and medium-temperature hydrothermal mineralization. It is the dimorph of enargite, rarer than the latter. It is particularly common in copper porphyry and gold-bearing epithermal deposits, where it accompanies numerous sulfides and sulfosalts (bornite, digenite, pyrite, enargite, tetrahedrite, etc...). Its name derives from its discovery location : the Lepanto mine on the island of Luzon (Philippines). Luzonite is generally massive, exceptionally in corroded crystals with curved faces of 2 mm maximum, constantly showing polysynthetic twins. It is dark reddish brown, dark purplish brown to steel gray in color. It is an accessory copper ore.

Main photo : Luzonite from Chinkuashih mine, Taiwan © Y. Okazaki

A twin is known on {112}.

No fakes recorded for this mineral species.