iron(ii) sulphate, a white or (when hydrated) pale green crystalline solid used in inks, tanning, water purification, and as a dietary supplement to…

An obsolete synonym of fibro-ferrite (see fibro-, comb._form).

A ferric sulphate of a yellow-brown or black colour and a resinous lustre.

Native ferrous sulphate, like copperas, but occurring in acicular crystals.