What is "zaratite"

Zaratite \Zar"a*tite\, n. (Min.) [Named after Gen. Zarata of Spain.] A hydrous carbonate of nickel occurring as an emerald-green incrustation on chromite; -- called also emerald nickel.

n. (context mineralogy English) a hydrous basic nickel carbonate occurring in emerald-green incrustations or compact masses

Zaratite is a bright emerald green and questionable nickel carbonate mineral with formula Ni C O(O H)·4 HO. Zaratite crystallizes in the isometric crystal system as massive to mammillary encrustations and vein fillings. It has a specific gravity of 2.6 and a Mohs hardness of 3 to 3.5. It has no cleavage and is brittle to conchoidal fracture. The luster is vitreous to greasy.

It is a rare secondary mineral formed by hydration or alteration of the primary nickel and iron bearing minerals, chromite, pentlandite, pyrrhotite, and millerite, during the serpentinization of ultramafic rocks. Hellyerite, NiCO·6HO, is a related mineral.

It was found originally in Galicia, Spain in 1851, and named after Spanish diplomat and dramatist Antonio Gil y Zárate (1793–1861).