Luzonite is a rare mineral that is dimorphous with Enargite. Luzonite forms in tetragonal crystals, while Enargite forms in orthorhombic crystals. Luzonite and Enargite sometimes form together in single altering crystals with different symmetry and cleavage habits.
Luzonite is named after its occurrence in Mancayan, Luzon Island, in the Philippines, which is the type locality for this mineral.