Class : Phosphates, arsenates, vanadates
    Subclass : Hydrated arsenates
    Crystal system : Monoclinic
    Chemistry : Ni₃(AsO₄)₂ 8H₂O
    Rarity : Rare

Cabrerite is a magnesian variety of annabergite (up to 6% MgO). Remember that annabergite is a rare secondary mineral from the oxidation zone of nickel-cobalt deposits where it results from the oxidation of skutterudite and cobaltite. Since cobalt can completely replace nickel, annabergite forms a continuous series with erythrite, which has the same crystal structure. Cabrerite takes its name from its place of discovery : La Sierra da Cabreira (Portugal). Like annabergite it never forms large crystals (maximum 10 mm): they are usually prismatic to acicular and striated according to [001]; it appears mainly in powdery coatings composed of fine flattened needles on {010}, in earthy aggregates, or in masses that can exceed a kilo. Adamantine luster, it has a pale green to apple green color which is its main criterion of distinction.

Main photo : Cabrerite from KM 3 Mines, Lavrion, Greece © Henry Minot

No twin known for this mineral species.

No fake identified for this mineral species.