omphacite

views updated

omphacite A rare clinopyroxene of isolated composition (Ca,Na)(Mg,Fe2+,Fe3+,A1) [Si2O6] and with similar properties to jadeite and augite; sp. gr. 3.16–3.43; hardness 5–6; green to dark green; massive or granular; occurs in eclogites at high temperatures and pressures in association with pyrope garnet.