Home > Mexico IV Ojuela II – January 19 > MS1750 Arseniosiderite after Arsenopyrite

Arseniosiderite after Arsenopyrite


Arseniosiderite is a complex hydrous calcium iron arsenate; its crystal structure remains unsolved to this day. Moore & Ito (1974) suggested that arseniosiderite has a crystal structure related to that of mitridatite, and proposed the currently accepted formula for the species. Dufrenoy (1842) named the species for its essential contents of arsenic and of iron, using Greek sideros for iron.

This is a curious specimen of arseniosiderite pseudomorphous after an undetermined precursor. While often assumed to replace scorodite, the habit of these crystals is closer to that of arsenopyrite. Both arsenopyrite and scorodite have orthorhombic symmetry. Another possiblity is double pseudomorphism of arseniosiderite after scorodite after arsenopyrite. Interesting! Well-formed for one of these.

Price: $150

Item code: MS1750

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