alunogen

[Fr. alun alum, and γεννάω (gennao) = to engender.] The name of a mineral; according to the British Museum Catalogue, the same as Keramohalite; but of the two names Dana prefers alunogen. He cla es it with "Oxygen Compounds-Hydrous Sulphates," and makes it the type of a group containing itself with Coquimbite. It generally occurs either in delicate fibrous crusts or ma ive. It is white, tinged with yellow or red, has a vitreous lustre, is sub-translucent or transparent, and tastes like alum. It is a sulphate of alumina, containing about 36-40 of sulphuric acid, 16 of alumina, and 46 of water. It is found near Bogota, and also in the vicinity of Königsberg.