Picropharmacolite
Picropharmacolite | ||
---|---|---|
2V angle 40° – 50° | | |
Dispersion | r < v strong | |
Other characteristics | Fluorescent blue-white under long wave and short wave ultraviolet light | |
References | [2][3][4][5] |
Picropharmacolite, Ca4Mg(AsO3OH)2(AsO4)2·11H2O, is a rare arsenate mineral. It was named in 1819 from the Greek for bitter, in allusion to its magnesium content, and its chemical similarity to pharmacolite. The mineral irhtemite, Ca4Mg(AsO3OH)2(AsO4)2·4H2O, has the same composition as picropharmacolite, except that it has only four water molecules per formula unit, instead of eleven. It may be formed by the dehydration of picropharmacolite.
Structure
Morphology
Picropharmacolite is usually found as small to microscopic pearly white botryoidal aggregates with a radiating foliated structure internally. Less commonly it occurs as silky fibrous aggregates or minute needle-like crystals, that are rectangular prisms elongated along the c axis.
Environment
Formed as an
Type locality
It was first described for samples from ore dumps of the Richelsdorf Smelter,
References
- S2CID 235729616.
- ^ a b Gaines et al (1997) Dana's New Mineralogy Eighth Edition, Wiley
- ^ a b c d http://rruff.geo.arizona.edu/doclib/hom/picropharmacolite.pdf Handbook of Mineralogy
- ^ a b "Picropharmacolite".
- ^ "Picropharmacolite Mineral Data".
- ^ American Mineralogist (1974) 59:807
- ^ American Mineralogist (1976) 61:326
- ^ American Mineralogist (1981) 66:385