|a green mineral consisting of the hydrated silicate of iron, potassium, aluminium, and magnesium: found in greensand and other similar rocks. Formula: (K,Na,Ca)0.5-1(Fe,Al,Mg)2(Si,Al)4O10(OH)2.nH2O|
|[C19: from Greek glaukon, neuter of glaukos bluish-green + |
greenish ferric-iron silicate mineral with micaceous structure [(K, Na)(Fe3+,Al, Mg)2(Si, Al)4O10(OmicronH)2], characteristically formed on submarine elevations ranging in depth from 30 to 1,000 metres (100 to 3,300 feet) below sea level. Glauconite is abundant only in sea-floor areas that are isolated from large supplies of land-derived sediment.
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