A yellowish green,
radiating mass of prismatic crystals in limonite.
A yellowish
mass of crystals.
A single
crystal of Adamite in limonite
Adamite from the Ojuela Mine, Mapami,
Durango, Mexico. Specimen is 2.5" across. Close-up view on the left.
CHEMISTRY Zn2(AsO4)(OH) Zinc arsenate
CRYSTALLOGRAPHY Orthorhombic
CRYSTAL GROWTH AND HABITS Adamite typically is dipyramidal with elongated prisms and sometimes tabular. Crystals often grow together in crusts or roughly radiating masses.
COLOR AND OTHER OPTICAL PROPERTIES Adamite is colorless or faintly tinted in yellow, green or pink. It is transparent to translucent.
HARDNESS 3.5
SPECIFIC GRAVITY 4.3 - 4.4
LUSTER Vitreous
STREAK White
BREAKABILITY Adamite has an uneven to subconchoidal fracture and brittle
OCCURRENCE Adamite forms as a secondary mineral in the oxidized zones of zinc and arsenic-bearing hydrothermal veins.
ASSOCIATED MINERALS Smithsonite, Calcite, Hemimorphite, Quartz