Characters. - Transparent scales, varying in colour from garnet-red to yellowish-brown, only slightly deliquescent, without odour, having a sweetish and slightly ferruginous taste and a neutral reaction.

Solubility. - It is readily soluble in water.

Reactions. - It is not precipitated by ammonia, but gives a brown precipitate of ferric oxide with potash and evolves the vapour of ammonia. On adding test solution of ferrocyanide of potassium to the salt, no blue colour or precipitate is produced unless the solution is acidulated with hydrochloric acid.