Images
Formula: Ca2Fe3+3(AsO4)3(OH)4.4H2O
Hydrated arsenate containing hydroxyl
Crystal System: Orthorhombic
Specific gravity: 2.65 measured
Hardness: 2 to 3
Streak: Brown
Colour: Red-brown, dark brown, nearly black, dark purple
Environments
Pegmatites
Hydrothermal environments
Yukonite occurs as an alteration of arsenic-rich minerals such as
arsenopyrite, köttigite and
parasymplesite in calcium-rich
oxidising environments
(Webmin).
Localities
At the type locality, the Daulton mine, Windy Arm, Tagish Lake, Carcross, Whitehorse mining district, Yukon, Canada,
yukonite occurs as black bright pitchy lumps with deep yellow to brown internal reflections, in
quartz-sulfide ore veins (Mindat). Associated minerals include
symplesite, silver-bearing
galena, pyrargyrite,
argentite, chalcopyrite,
arsenopyrite and quartz
(HOM).
At Grotta della Monaca, Sant'Agata di Esaro, Cosenza Province, Calabria, Italy, yukonite occurs in compact
masses, dark reddish brown to brownish yellow in colour, occasionally admixed with
scorodite
(CM 47.39-51).
At the Dolomite quarry, Rędziny, Gmina Kamienna Góra, Kamienna Góra County, Lower Silesian Voivodeship, Poland,
yukonite occurs with arsenopyrite and
pharmacosiderite
(HOM).
At the Trout Creek Pass pegmatite District, Buena Vista, Chaffee county, Colorado, USA, yukonite occurs
with arsenopyrite,
arseniosiderite, arsenolite
and bariopharmacosiderite
(HOM).
At the Sterling Mine, Sterling Hill, Ogdensburg, Franklin Mining District, Sussex County, New Jersey, USA,
yukonite occurs as gel-like, waxy aggregates of brownish color and dark red, remnant
pseudomorphs after
köttigite-parasymplesite
(AM 64.475). Associated minerals include parasymplesite,
köttigite, ogdensburgite,
pharmacosiderite, legrandite,
willemite, franklinite and
sphalerite
(HOM).
Back to Minerals