Mineral description : Gold

Alluvial gold from Bjurholm, Västerbotten. In copper sulfate.

Gold from the Björkdal mine. It's visible in the bigger picture as yellow dots on the pyrite.

Gold in quartz from the Björkdal mine. As filling in fractures.

Mineral class	Elements : Copper-silver-gold group
Chemical formula	Au
Crystal system	Cubic
Habitus	As grains, crack fillings and jugs. Rarely as octaedric crystals.
Cleavage	None, malleable.
Hardness	2.5-3
Density	19.3
Color	Yellow, without tarnish.
Streak	Yellow shiny.
Luster	Metallic
Description
Occurance	Primarily in quartz veins of hydrothermal origin, but also as magmatic and metamorphic rock. Concentrated in alluvial deposits.
Associates	Quarts, sulfides.
Notes	Soluble in aqua regia, not in nitric acid. Norhern Sweden is the biggest gold producer in Europe.
Locations	Boliden mine, Västerbotten. Sometimes as visual flakes. Björkdalsgruvan, Västerbotten. In quarts veins together with tsumoite. Falu mine. With Pb-Bi-Sb sulfides, sometimes visible. Ädelfors mine, Jönköping län. In quartz veins. Fridhems mine, Gällivare, Norrbotten. Together with zeolites in quartz-calcite veins.

To elements index.

Mineral group index.

Main index.

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