Beudantite
| Beudantite | ||
|---|---|---|
Specific gravity 4.48 | | |
| Optical properties | Uniaxial (−) | |
| Refractive index | nω = 1.957 nε = 1.943 | |
| Birefringence | δ = 0.014 | |
| Pleochroism | visible | |
| Other characteristics | Soluble in HCl | |
| References | [2][3][4] | |
Beudandite is a secondary mineral occurring in the
oxidized zones of polymetallic deposits.[4] It is a lead, iron, arsenate, sulfate with endmember formula
: PbFe3(OH)6SO4AsO4.
Beudantite is in a subgroup of the alunite group. It is the arsenate analogue of the phosphate corkite. Beudantite also forms a solid-solution with segnitite and plumbojarosite.[2]
It crystallizes in the
trigonal crystal system and shows a variety of crystal habits
including tabular, acute rhombohedral, pseudo-cubic and pseudo-cuboctahedral.
It occurs in association with carminite, scorodite, mimetite, dussertite, arseniosiderite, pharmacosiderite, olivenite, bayldonite, duftite, anglesite, cerussite and azurite.[4]
Discovery
Beudantite was first described in 1826 for an occurrence in the Louise Mine, Wied Iron Spar District, Westerwald, Rhineland-Palatinate, Germany. It was named by Armand Lévy after his fellow Frenchman and mineralogist François Sulpice Beudant (1787–1850).[2]
See also
References
Wikimedia Commons has media related to Beudantite.
- S2CID 235729616.
- ^ a b c Mindat.org
- ^ Web Mineral data
- ^ a b c Handbook of Mineralogy