A silicate of aluminium, sodium, and calcium found in brownish-pink crystals. Also = gmelinite, n.

An amorphous clay mineral, typically pale blue, consisting essentially of hydrated aluminium silicate.

Hydrous silicate of aluminium, calcium, and sodium, found in colourless, yellow, and brownish-pink crystals.

A silicate of aluminum and calcium, found in colourless or slightly tinted tabular crystals.

A name formerly applied to greenish opaline specimens of allophane.

= levyne, n.

A colourless glassy aluminosilicate of calcium and sodium with the composition of plagioclase, found in certain kinds of meteorite.

A name given to the serpentine pseudomorphs found at Snarum, in Norway.

A mineral consisting essentially of silica in a fibrous form, more or less impregnated with iron, forming the gem known as tiger eye.

= tiger's-eye n. at compounds 2b.

A mineral of the monoclinic crystal system which consists of a hydroxide and aluminosilicate of manganese, and occurs as minute orange-red…

A monoclinic hydrated silicate of calcium, magnesium, and aluminium found as white aggregates or masses.