Search results
Results from the WOW.Com Content Network
Quartz and calcite crystals up to 6 inches (150 mm) long were common and pyrites covered with euhedral gold crystals were found in 60% of the veins. A remarkable sample of a cubic pyrite crystal from the Crystal Mine, which measures about 3 inches (76 mm) on a side with large amount of terminated crystals of gold on its surface, is on display ...
The Willow Creek mining district, also known as the Independence Mine/Hatcher Pass district, is a gold-mining area in the U.S. state of Alaska. Underground hard-rock mining of gold from quartz veins accounts for most of the mineral wealth extracted from the Hatcher Pass area. The first mining efforts were placer mining of stream gravels, and ...
Most of the gold recovered from the Admiralty mining district (which consists of Admiralty Island) is a by product of silver and base metal mining. The Alaska Empire underground lode mine recovered gold from quartz veins in metamorphic rocks. Discovered and staked in the 1920s, production of about 20,000 tonnes of 0.25 ounce-per-ton gold ore ...
Gold mining in Egypt involved both surface mining such as panning for gold in riverbeads and underground mining, where tunnels were dug to extract gold-bearing quartz veins. [6] During the Bronze Age, sites in the Eastern Desert became a great source of gold-mining for nomadic Nubians, who used "two-hand-mallets" and "grinding ore extraction."
The Sibelco mine in North Carolina is one of the most crucial sites to the global production of semiconductors.
The company sells its quartz under the brand name IOTA. Its mines are north of downtown in an area called the Spruce Pine Mining District. On Google Maps they look like wide, white sandy beaches.
Copper-bearing quartz veins occur in greenstone schist along a narrow belt stretching four miles NNE-SSW from Keysville on the north to Virgilina on the North Carolina border. The Barnes mine is reported to have produced some copper in the early 18th century, but the major productive era for the district was the late 19th century to 1917. [68]
The stockwork zone typically consists of vein-hosted sulfides (mostly chalcopyrite, pyrite, and pyrrhotite) with quartz, chlorite and lesser carbonates and barite. The mound zone consists of laminated massive to brecciated pyrite, sphalerite (± galena), hematite, and barite. The mound can be up to several tens of metres thick and several ...