What is "erythrite"

Erythrite \E*ryth"rite\, n. [Gr. 'eryqro`s red.]

1. (Chem.) A colorless crystalline substance, C4H6.(OH)4, of a sweet, cooling taste, extracted from certain lichens, and obtained by the decomposition of erythrin; -- called also erythrol, erythroglucin, erythromannite, pseudorcin, cobalt bloom, and under the name phycite obtained from the alga Protococcus vulgaris. It is a tetrabasic alcohol, corresponding to glycol and glycerin.

2. (Min.) A rose-red mineral, crystallized and earthy, a hydrous arseniate of cobalt, known also as cobalt bloom; -- called also erythrin or erythrine.

n. (context mineral English) Red cobalt, a secondary hydrated arsenate of cobalt minerals with the formula (Co₃(AsO₄)₂·8H₂O).

n. a reddish mineral consisting of hydrated cobalt arsenate in monoclinic crystalline form and used in coloring glass; usually found in veins bearing cobalt and arsenic [syn: cobalt bloom]

Erythrite or red cobalt is a secondary hydrated cobalt arsenate mineral with the formula (Co(AsO)·8HO). Erythrite and annabergite (Ni(AsO)·8HO) ( nickel arsenate) form a complete series with the general formula (Co,Ni)(AsO)·8HO.

Erythrite crystallizes in the monoclinic system and forms prismatic crystals. The color is crimson to pink and occurs as a secondary coating known as cobalt bloom on cobalt arsenide minerals. Well-formed crystals are rare, with most of the mineral manifesting in crusts or small reniform aggregates.

Erythrite was first described in 1832 for an occurrence in Grube Daniel, Schneeberg, Saxony, and takes its name from the Greek έρυθρος (erythros), meaning red. Historically, erythrite itself has not been an economically important mineral, but the prospector may use it as a guide to associated cobalt and native silver.

Erythrite occurs as a secondary mineral in the oxide zone of Co–Ni–As bearing mineral deposits. It occurs in association with cobaltite, skutterudite, symplesite, roselite-beta, scorodite, pharmacosiderite, adamite, morenosite, retgersite, and malachite.

Notable localities are Cobalt, Ontario; Schneeberg, Saxony, Germany; Joachimsthal, Czech Republic; Cornwall, England; Bou Azzer, Morocco; the Blackbird mine, Lemhi County, Idaho; Sara Alicia mine, near Alamos, Sonora, Mexico; Mt. Cobalt, Queensland and the Dome Rock copper mine, Mingary, South Australia.