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Formula: Fe3+(AsO4).2H2O
Hydrated normal arsenate,
variscite group, forms a series with
mansfieldite and with
yanomamite.
Crystal System: Orthorhombic
Specific gravity: 3.27 measured, 3.276 calculated
Hardness: 3½ to 4
Streak: Greenish-White
Colour: Green, grey, blue, yellow-brown, nearly colourless, violet; colourless to greenish or in transmitted light.
Solubility: Soluble in acids. Decomposes in strong alkali with separation of hydrous iron oxide.
Common impurities: Al
Environments
Pegmatites
Hydrothermal environments
Scorodite is found sometimes as a primary mineral at hydrothermal deposits,
for example Saubach, Germany, but mostly as a
secondary mineral.
It is a common supergene mineral in areas where
primary arsenopyrite-bearing
mineralisation is present. It may be the only
supergene species present, or in more evolved oxidised deposits it may occur
accompanied by pharmacosiderite and a range of base-metal arsenates. It occurs
typically as discernably crystalline crusts on part-weathered, crumbly and cracked arsenopyrite
(MW).
It forms from the oxidation of
arsenopyrite or other arsenic-containing minerals, and is associated with
pharmacosiderite, beudantite,
carminite, dussertite,
arseniosiderite, adamite,
austinite,
vivianite, gypsum and
chalcedony
(Dana, HOM).
Localities
At Kingsgate, Gough county, New South Wales, Australia, scorodite is formed by the oxidation of
arsenopyrite, and occurs as druses on arsenopyrite
and quartz
(AJM 10.1.10-11).
At Sunny Corner, Roxburgh county, New South Wales, Australia, scorodite is associateted with
beudantite, and occasionally with
bariopharmacosiderite. Scorodite forms first, then
beudantite, then bariopharmacosiderite
(AJM 17.1.48).
At Kintore, Broken Hill, Broken Hill district, Yancowinna county, New South Wales, Australia, scorodite occurs in a
quartz - garnet rock, sometimes with included
carminite. It has also been found rarely as a scorodite -
strengite crust on hinsdalite
(AJM 3.1.62).
At a prospect on Mount Piper near Broadford, Victoria, Australia, crusts of tiny scorodite crystals occur with
arsenopyrite and quartz
(R&M 85.3.242-248).
At Mount Moliagul, Moliagul, Central Goldfields Shire, Victoria, Australia, botryoidal crusts and groups of
scorodite up to 5 mm have been found in cavities in quartz, associated
with pyrite, arsenopyrite and
jarosite - natrojarosite
(AJM 21.1.44).
At a point about 10 kilometers west of L’Amable Station on the Central Ontario Railway, Hastings County, Ontario, Canada,
scorodite occurs with arsenopyrite,
realgar, and quartz
(R&M 85.3.242-248).
At the Brazil Lake occurrence (Elizabeth Lake Mine), Foster Township, Sudbury District, Ontario, Canada, scorodite
pseudomorphs after cobaltite to
1 cm have been collected
(R&M 85.3.242-248).
At Chuquicamata Mine, Chuquicamata District, Calama, El Loa Province, Antofagasta, Chile, scorodite is an accessory mineral,
apparently after enargite of the primary
ore
(R&M 85.3.242-248).
At the Pingtouling mine, Liannan county, Qingyuan, Guangdong, China, colour-change scorodite lines cavities in
limonite, associated with anglesite, arsenic-bearing
siderite and beudantite
(Minrec 38.1.30 ).
At the Clara Mine, Oberwolfach, Ortenaukreis, Freiburg Region, Baden-Württemberg, Germany, fine specimens of
secondary scorodite occur. Spherical clusters to 1 cm abundantly
perched on quartz crystals and fluorite cubes have
been found. Ferrihydrite pseudomorphs
after scorodite have also been found here
(R&M 90.1.47).
The type locality is the Stamm Asser Mine, Graul, Langenberg, Raschau-Markersbach, Erzgebirgskreis, Saxony, Germany.
At Mapimí, Mapimí Municipality, Durango, Mexico, two forms of scorodite were found, one in coarse granular masses with numerous small
vugs of crystals, and the other in rounded concretionary masses of compact material abundantly veined by
arseniosiderite, or with pockets and cavities of
carminite and dussertite
(AM 22.482).
At the Ojuela Mine, Mapimí, Mapimí Municipality, Durango, Mexico, scorodite is associated with
carminite, dussertite,
arseniosiderite, legrandite,
adamite and arsenopyrite
(R&M 85.3.242-248).
At Oumlil, Zagora Province, Drâa-Tafilalet Region, Morocco, scorodite occurs as 1 mm spherules associated with weathered
löllingite, and as world-class colour-change crystals to 15 cm
(Minrec 38.5.394).
At Tamdrost, Zagora Province, Drâa-Tafilalet Region, Morocco, scorodite crystals to 3 mm have been found forming coatings on
erythrite crystals
(Minrec 38.5.394).
At the Tsumeb Mine, Tsumeb, Oshikoto Region, Namibia, crystals of scorodite resembling elongate octahedra to 5 cm occur
with a suite of rare minerals including betpakdalite,
powellite and gerdtremmelite
(R&M 85.3.242-248).
At the Stavoren Mine, Stavoren-Mute Fides, Marble Hall, Sekhukhune District, Limpopo, South Africa, scorodite was found
intimately associated with arsenopyrite
(R&M 85.3.242-248).
At Burdell Gill, Coombe Height, Caldbeck, Allerdale, Cumbria, England, UK, bladed aggregates of scorodite, less than 0.1 mm, on
iron-stained quartz were shown by XRD to be scorodite; they appear to be
pseudomorphs after parasymplesite. In
the wolframite-bearing quartz vein material from lower down Burdell Gill drusy
scorodite occurs with residual arsenopyrite
(JRS 8(1).6).
At the Driggith and Sandbed mines, Caldbeck, Allerdale, Cumbria, England, UK, scorodite occurs abundantly as drusy encrustations
with bariopharmacosiderite, beudantite,
carminite and minor mimetite on specimens from
arsenate-rich outcrop workings on the vein between the Driggith and Sandbed mines. Epimorphs
of scorodite after arsenopyrite occur on a few specimens
(JRS 9.31).
At the east side of higher Roughton Gill, Caldbeck, Allerdale, Cumbria, England, UK, scorodite occurs as crusts which are part
of an arsenate-rich assemblage that also includes beudantite,
carminite and segnitite
(JRS 11.22).
At Arm O'Grain, Coombe Height, Mungrisdale, Eden, Cumbria, England, UK, scorodite was identified by XRD as crusts in hairline
fractures in the arsenopyrite- and pyrite-rich
rock
(JRS 9.51).
At the Dolaucothi Gold Mine, Pumpsaint, Carmarthenshire, Wales, UK, scorodite occurs rarely as coatings on part-weathered
arsenopyrite
(MW).
At the Dolgellau Goldbelt, Gwynedd, Wales, UK, scorodite is widespread in trace to minor amounts. It has been found at Clogau,
Vigra, Cefn Coch, Tyddyn Gwladys and Prince Edward mines, and in pyrite -
arsenopyrite bearing boulders in the bed of the Afon Wen. In the Foel Ispri mines, near
Llanelltyd, sub-millimetre crusts fill small cavities in pyrite -
arsenopyrite rich veinstone
(MW).
At Gwaith-yr-Afon Mine, Goginan, Ceredigion, Wales, UK, sparsely scattered crystal aggregates of scorodite have been found associated
with limonite and pharmacosiderite on
quartz
(MW).
At Snowdon, Gwynedd, Wales, UK, scorodite is present at mines around the caldera margin, such as Cwm Bychan near Beddgelert, Llanberis,
Moel Fleiddiau near Blaenau Ffestiniog and Ceunant and Tan-y-garth mines near Bethesda. Typically it forms thin microcrystalline crusts
in association with iron oxides on decomposing arsenopyrite
(MW).
At the California Mine (Great Eastern Mine), Summit City, Meadow Lake District, Nevada county, California, USA, scorodite containing
native gold is locally abundant
(R&M 85.3.242-248).
At the Crystal No. 8 Mine, Chaffee county, Colorado, USA, scorodite is found in the exposed pegmatite where it occurs with
yukonite, bariopharmacosiderite,
and arsenopyrite
(R&M 85.3.242-248).
At the Charter Oak Mine, Red Mountain District, Ouray county, Colorado, USA, scorodite encrusts
enargite
(R&M 85.3.242-248).
At the Eagle Bird Mine, Garfield Canyon, and the Idaho Muldoon Mine, both at the Little Wood River District, Blaine county, Idaho, USA,
scorodite occurs as microcrystalline crusts associated with anglesite and
cerussite
(R&M 85.3.242-248).
Near Black Pine, Black Pine District, Cassia county, Idaho, USA, prismatic crystals of scorodite form botryoidal
aggregates with cinnabar
(R&M 85.3.242-248).
At the Emmons pegmatite, Greenwood, Oxford county, Maine, USA, scorodite is rare and has been found as crystals less than
one millimetre across coating löllingite masses
(R&M 94.6.515).
At the San Rafael mine, Quartz Mountain camp, Lodi Mining District, Lodi Hills, Nye county, Nevada, USA, scorodite occurs either
as massive intergrowths or as spongy, finegrained nodules. Associated minerals include
arseniosiderite, anglesite,
bayldonite, beudantite,
carminite, galena,
mimetite, plumbojarosite and
segnitite. In the stope where pharmacosiderite
has been found, peculiar masses to several kilograms in weight consisting almost entirely of very finely crystalline scorodite have
been found. In this same stope, well-formed crystals of scorodite to 0.1 mm on limonite
have also been found, but they are rare
(R&M 85.6.520).
At the Majuba Hill Mine, Antelope Mining District, Pershing county, Nevada, USA, scorodite occurs as attractive groups of
2-mm sky-blue crystals associated with pharmacosiderite,
arthurite and chalcocite
(R&M 85.3.242-248).
At the Chickering mine, Walpole, Cheshire county, New Hampshire, USA, scorodite has been found as a crust covering
the surface of corroded arsenopyrite and löllingite
in the single known occurrence
(R&M 90.5.420).
At the Miss Pickle Tunnel, Eureka Mining District, Grant county, New Mexico, USA, scorodite has been found as liver-brown masses,
rarely forming pseudomorphs after arsenopyrite
(R&M 85.3.242-248).
At the pegmatite at the November Mine, Needles, Custer county, South Dakota, USA, scorodite occurs with
spessartine and arsenopyrite
(R&M 85.3.242-248).
At the Richmond-Sitting Bull Mine, Galena Mining District, Lawrence county, South Dakota, USA, excellent though small scorodite
crystals occur with beudantite and pharmacosiderite
(R&M 85.3.242-248).
At Gold Hill, Toole County, Utah, USA, scorodite forms bodies of considerable magnitude as an alteration product of
arsenopyrite
(AM 15.390).
At the Crystal Palace claim, North Bend, King county, Washington, USA, scorodite is found as bright greenish
crusts with quartz crystals, pyrite and
arsenopyrite
(R&M 85.3.242-248).
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