The arsenite minerals are rare since the arsenic has a 3+ oxidation state as it combines with oxygen (2- oxidation state). The resulting anion is usually AsO3 with an oxidation state of 3-. Example, ludlockite
|Silvery, metallic, massive löllingite in a matrix of albite (with some iron staining). Width FOV ~3 cm.|
|Photomicrograph of a portion of above specimen from Bob Ingersoll Mine. Width FOV ~ 1.6 cm.|
|Photomicrograph of slightly iridescent löllingite along with non-tarnished löllingite in upper third and a nice (partially covered) gemmy blue elbaite tourmaline (indicolite variety) in lower left corner. Width FOV ~1.2 cm.|
löllingite. Width FOV ~1.0 cm.
|Elbaite crystal encased in muscovite. Length of crystal ~2.8 cm. Note triangular cross section of a third crystal above.|
|Nicely striated elbaite crystals weathered out of muscovite matrix. Width FOV ~2.4 cm.|