Gaspeite

Gaspeite is a rare nickel carbonate mineral with the formula (Ni,Mg,Fe)CO3, in which nickel is the dominant cation and magnesium and iron substitute for nickel. It forms as green to apple-green masses or crystals and typically has a vitreous to pearly luster. It is usually translucent to opaque and has a white streak; its hardness is around 4 on the Mohs scale.

Gaspeite commonly forms in oxidized zones of nickel-rich ultramafic rocks and is sometimes found in association with other nickel minerals and carbonates. It has also been reported from meteorites as a secondary carbonate phase, reflecting its occurrence beyond terrestrial rocks.

The mineral is named after the Gaspe Peninsula in Quebec, Canada, which is the locality where it was first described. The Gaspe Peninsula remains the type locality, and gaspeite is prized by mineral collectors for its distinctive bright green color. While it can occur in small amounts, it is not a major ore of nickel, and its value rests primarily in its rarity and aesthetics.