Chalcopyrite, unknown locality but probably Skellefteå mining field.
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Chalcopyrite from Alnö area.All crystals damaged, but one face remains showing striation. |
Chalcopyrite from Alnö area.A few crystals, one big (6mm) showing heavy twinning. |
| Mineral class | Sulphides : Chalcopyrite - Bornite broup |
| Chemical formula | CuFeS2 |
| Crystal system | Tetragonal. |
| Habitus | Small flat tetraedic crystals, often twinned and with striations on the crystal faces. More often as massive or grainy aggregates. |
| Cleavage | Poor, uneven to conchoidal cleavage. |
| Hardness | 3.5-4 |
| Density | 4.3-4.4 |
| Color | Yellow, deeper than pyrite. Often with irisdescent tarnish. |
| Streak | Greenish black. |
| Luster | Metallic, opaque. |
| Description | One of the most important ores of copper. |
| Occurance | Forms with sulphide ores, in hydrothermal veins, in magmatic rocks. More rarely in pegmatites or metamorphic rocks. |
| Associates | Pyrrhotite, quartz, calcite, pyrite, sphalerite, galena. |
| Notes | Soluble in nitric acid. Colors a flame green. |
| Locations | A very common mineral with a number of mines in Sweden,
primarily in Bergslagen and Skellefteå field. Crystals are more rare but can also be found.
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| To sulphides index. |
Mineral group index. |
Main index. |
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