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Download hereGENERAL DESCRIPTION
Anglesite is an abundant lead sulphate in a microscopic state on the surface of many galena (lead sulphide) but remains rare in beautiful macroscopic crystals. It can be found with cerusite and pyromorphite in the zones of oxidation of the lead deposits by oxidation of galena.
Anglesite displays prismatic crystals, sometimes tabular, pointing out those of barite. The crystals, generally colourless, very often have clear edges and highly reflective faces. The crystals of anglesite coloured in blue or green are particularly rare and very appreciated by mineral collectors and museums Their colour is due to the presence of copper impurities.
Another characteristic of this mineral is its yellow fluorescence when it is exposed to ultraviolet (UV) light.
Anglesite is seldomly fiund as centimetric crystals. The most beautiful samples come from the mines of Touissit, close to Oujda (Morocco), of Tsumeb (Namibia), Sidi-Amor-Ben-Salem (Tunisia) and Monteponi in Sardinia (Italy). In these deposits, anglesite is colourless to yellow and the multidecifoundric crystals (up to 50 cm) are weighing several kilos.
In the years 1980, anglesite crystals, remarkable by their yellow colour orange, appeared coming from the mine of Touissit. If anglesite came well from this deposit, the colour had been obtained artificially by bleaching the samples. In France, it is rare as subcentimetric crystals. Major localities are the mines of Huelgoat or Poullaouen in Finistere, the mine of Ar in the Pyrénées-Atlantiques, the mine of Réalmont in the Tarn and more recently the mine of Laval close to Masdieu, in the Gard. It was found in significant quantities, but generally massive, in the zone of oxidation of the lead-zinc deposit of St. Felix de la Pallière in the Gard.
The species was described by F.S. Beudant in 1832, in a sample present in the personal collection of the king Louis XVIII (old collection of Bournon) and coming from the island of Anglesey in Scotland.
The types of the species resulting from the study of Beudant are to the Muséum national d'Histoire naturelle of Paris in one of the 24 pieces of furniture carried out by the workshop Jacob-Desmalter and which lodge the few 15.000 samples of the collection of the king Louis XVIII.
HISTORY : Named after its type-locality : Anglesey island, UK
Species named en 1832 by François-Sulpice Beudant (1787-1850), French mineralogist and geologist, by redescribing the species from samples of the Jacques-Louis de Bournon private collection (1751-1825)
Type-locality: Mine Parys, Ile d’Anglesey, Pays de Galles
ANCIENT NAME : Plomb vitriol, plomb sulfaté
CHEMICAL FORMULA : Pb SO4
CRYSTAL SYSTEM : Orthorhombic
COLOR : Colorless, white, yellowish, gray
DIAPHANIETY : Transparent to translucent
LUSTER : Adamantine, resineous, vitreous
STREAK : White
MORPHOLOGIE : Tabular crystals, isometric prismatic, forming aggregates
HARDNESS : 2,5-3,0
CHEMICAL CLASS: 6,36
DENSITY : VI - Sulfates, chromates, tungstates and molybdates
GROUP : Barytine
STRUNZ CLASS BEFORE 2001 : 6/A.09-50
STRUNZ CLASS AFTER 2001 : 7.AD.35
