Berryite

berryite

aikinite

galena

matildite

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Formula: Cu3Ag2Pb3Bi7S16
Sulphosalt, bismuth-bearing mineral
Crystal System: Monoclinic
Specific gravity: 6.7 measured, 6.83 calculated
Hardness: 3½
Colour: Bluish grey, white, grey-white
Environments

Hydrothermal environments

Localities

There are two co-type Localities, Nordmark Odal Field, Filipstad, Värmland County, Sweden, and the Missouri mine, Hall Valley, Montezuma Mining District, Park County, Colorado, USA.

At Owen Lake, Omineca Mining Division, British Columbia, Canada, the principal ore minerals are pyrite and sphalerite with galena, chalcopyrite and tennantite occurring in smaller amounts. Other ore minerals that occur in small to trace amounts include tetrahedrite, matildite, native gold, marcasite, aikinite, hematite, rutile, anatase, ilmenite, magnetite and goethite.
The gangue minerals are chiefly quartz and manganese-bearing siderite with mica, dolomite, apatite and baryte occurring as inclusions in the quartz.
Berryite in the ore is very sparse and was observed only in chalcopyrite-rich samples. Berryite occurs as irregular sheaf-like aggregates and as regularly-developed laths associated with aikinite, intergrown with galena - matildite, and occasionally as irregular grains in chalcopyrite, tennantite and gangue. The grain sizes of berryite and aikinite are similar and range from 0.1 to 1.2 mm. The matildite is intergrown with galena (CM 11.5.1016-1018).

At the Ivigtut mine, Ivittuut town, Arsuk Fjord, Sermersooq, Greenland, berryite was found in the cryolite mine together with both ore and gangue minerals as small massive lumps in the siderite-rich cryolite. The gangue minerals include fluorite and topaz with minor weberite, and quartz.
The ore minerals include cosalite, galena, aikinite and berryite. Insignificant amounts of chalcopyrite, sphalerite, pyrrhotite, marcasite, pyrite and native bismuth are also present.
Berryite is often replaced by galena (CM 8.4.414-423).

At Nordmark Odal Field, Filipstad, Värmland County, Sweden, one of the type localities, berryite is associated with galena, chalcopyrite, sphalerite and quartz (HOM).

At the Tary-Ekan Pb-Zn deposit, East Karamazar ore district, Adrasmon, Ghafurov District, Sughd, Tajikistan, berryite is associated with aikinite, matildite, benjaminite, quartz and baryte (HOM).

At the Missouri Mine, Hall Valley, Montezuma Mining District, Park County, Colorado, USA, one of the type localities, berryite is associated with emplectite, aikinite, cuprobismutite and cupropavonite (HOM).

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