Chalcocite from
Bristol Copper Mine, Bristol, Hartford County, Connecticut, USA
| Locality type: | Mine | |
| Classification | ||
|---|---|---|
| Species: | Chalcocite | |
| Formula: | Cu2S | |
| Formation: | Primary | |
| Comments: | Tabular to elongated, usually singly or multiply twinned crystals with a bluish, lustrous metallic luster when fresh, up to 2 or 3 cm long. Usually associated with scalenohedral calcite and/or milky quartz. Crystals gradually gain a black charcoal coating that is easily cleaned by placing them in an agitated alconox solution, which does not harm the crystals or associated minerals. | |
| Habit: | Orthorhombic crystals, many showing twinning. Some are heavily striated, often show a pseudohexagonal symmetry, and discoidal pseudohexagonal crystals are common. Tabular crystals also occur in abundance. Twinned crystals may be pseudohexagonal, or may b | |
| Colour: | metallic bluish-black | |
| Quality for species: | Excellent - world class for species or very significant. (!!) | |
| Significance: | "Dana Locality" - A locality listed in 19th century editions of Dana's 'System of Mineralogy.' | |
| Abundance at site: | Very common | |
| Confirmation | ||
| Validity: | Believed Valid | |
| Associated Minerals Based on Photo Data: | ||
| Calcite | 63 | |
| Quartz | 19 | |
| Bornite | 5 | |
| Malachite | 5 | |
| Siderite | 2 | |
| Djurleite | 1 | |
| Chalcopyrite | 1 | |
| - var Blistered Copper | 1 | |
| Data | ||
| Mineral Data: | Click here to view Chalcocite data | |
| Locality Data: | Click here to view Bristol Copper Mine, Bristol, Hartford County, Connecticut, USA | |
| Photo Gallery | View Gallery (99 photos) | |
| Data Identifiers | ||
| Mindat Occurrence Record ID: | 3410 | |
| Long-form Identifier: | 1:3:3410:4 | |
| GUID (UUID V4): | 0 | |
| Nearest other occurrences of Chalcocite | ||
| 14.6km (9.1 miles) | ⓘState Route 9 - Ellis Street and State Route 72 interchanges (State Route 72 roadcut), New Britain, Hartford County, Connecticut, USA | |
| 18.3km (11.4 miles) | ⓘInterstate 691 and State Route 10 Interchange, Cheshire, New Haven County, Connecticut, USA | |
| 20.6km (12.8 miles) | ⓘPillow lava locality, Meriden, New Haven County, Connecticut, USA | |
| 22.2km (13.8 miles) | ⓘCheshire Barytes Company barite mine (Stamford Manufacturing Company barite mine), Cheshire, New Haven County, Connecticut, USA | |
| 24.3km (15.1 miles) | ⓘRocky Hill Quarry, Rocky Hill, Hartford County, Connecticut, USA | |
| 26.4km (16.4 miles) | ⓘCopper Valley Mine, Cheshire, New Haven County, Connecticut, USA | |
| 27.0km (16.8 miles) | ⓘJinny Hill Mine (Cheshire Barite Mine), Cheshire, New Haven County, Connecticut, USA | |
| 28.1km (17.4 miles) | ⓘCross Rock Copper Mine, Cheshire, New Haven County, Connecticut, USA | |
| 30.7km (19.1 miles) | ⓘSimsbury Mines, East Granby, Hartford County, Connecticut, USA | |
| 30.8km (19.1 miles) | ⓘNew-Gate Copper Mine (Old New-Gate Prison), Simsbury Mines, East Granby, Hartford County, Connecticut, USA | |
| References | ||
Bateman, Alan Mara (1923) Primary chalcocite: Bristol copper mine, Connecticut. Economic Geology, 18 (2). 122-166 doi:10.2113/gsecongeo.18.2.122 Sagui, Cornelio Leone (1923) Primary chalcocite; Bristol, Conn.; discussion. Economic Geology, 18 (7) 699-700 doi:10.2113/gsecongeo.18.7.699 | ||
Bristol Copper Mine, Bristol, Hartford County, Connecticut, USA