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1. 2 Responses to “I need a simple description of the process of gold mining during the Klondike Gold Rush?”

2. By gold dredges on Jul 13, 2009 | Reply

   Gold Panning

   Gold panning is a mostly manual technique of sorting gold. Wide, shallow pans are filled with sand and gravel that may contain gold. Water is added and the pans are shaken, sorting the gold from the gravel and other material. As gold is much denser than rock, it quickly settles to the bottom of the pan. The silt is usually removed from stream beds, often at a bend in the stream, or resting on the bedrock bed of the stream, where the weight of gold causes it to separate out of the water flow. This type of gold found in streams or dry streams are called placer deposits.

   Gold panning is the easiest technique for searching for gold, but is not commercially viable for extracting gold from large deposits, except where labor costs are very low and/or gold traces are very substantial. It is often marketed as a tourist attraction on former goldfields. Before production methods can be used, a new source must be identified and panning is a good way to identify placer gold deposits so that they may be evaluated for commercial viability.

   Metal detecting

   With a metal detector, a person may walk around area systematically scanning below the surface. If the meter gives a positive reading a quantity of gold may be present up to a meter below the surface. This technique is very easy to operate, highly mobile, and very popular among gold diggers.

   Sluicing

   Using a sluice box to extract gold from placer deposits has been a common practice in prospecting and small-scale mining throughout history to the modern day. A sluice box is essentially a man-made channel with riffles set in the bottom. The riffles are designed to create dead zones in the current to allow gold to drop out of suspension. The box is placed in the stream to catch water-flow and gold bearing material is placed at the top of the box. The material is carried by water through the box where gold and other heavy material settles out behind the riffles. Lighter material flows out of the box as tailings.

   Larger commercial placer mining operations employ screening plants or trommels to remove the larger alluvial materials such as boulders and gravel before concentrating in a sluice box or jig plant. These operations typically include diesel powered earth moving equipment including excavators, dozers, wheel loaders and rock trucks.

   Dredging.

   Although mostly historical, some dredging is done by small scale miners using suction dredges. These are small machines floating on the water and are usually operated by one or two people. A suction dredge consists of a sluice box supported by pontoons, and attached to a suction hose which is controlled by the miner working beneath the water. Some believe that modern suction dredges have a significant environmental impact to fisheries by disturbing spawning gravels and fish migration. However, most small scale dredging operations affect the local fish only by stirring up additional food from the bottom of the river. These machines are much more efficient at extracting smaller gold than the old “bucket line” ever was. This means there is a better chance of finding gold than ever. There are some large suction dredges (100 hp+ 10 inch) used in commercial production throughout the world. Smaller ones with 2 to 4-inch (100 mm) suction tubes are used to sample the areas behind boulders and along the potential pay streaks, until color (gold) first appears.

   Other larger scale dredging operations take place on exposed river gravel bars at seasonal low water. These operations typically use a land based excavator to feed a gravel screening plant and sluicebox floating in a temporary pond excavated in the gravel bar and filled from the natural water table. Pay gravel is excavated from the front face of the pond and processed through the floating plant, with the gold trapped in the onboard sluicebox and tailings stacked behind the plant, steadily filling in the back of the pond as the operation moves forward. This kind of gold mining is characterized by its low cost, as each rock is moved only once, as well as by its low environmental impact, as no stripping of vegetation or overburden is necessary, and all process water is fully recycled. These operations are typical on New Zealand’s south island and in the Klondike region of Canada.

   Hard rock mining

   Hard rock gold mining is done when the gold is encased in rock, rather than as particles in loose sediment. Sometimes open-pit mining is used, such as the Ft. Knox Mine in central Alaska. Barrick Gold Corporation has one of the largest open-pit gold mines in North America, located on its Goldstrike property in northeastern Nevada. Other gold mines use underground mining, where the ore is extracted through tunnels or shafts. Hard rock mining produces most of the world’s gold

   Byproduct gold mining

   Gold is also produced by mining in which it is not the principal product. Large copper mines, such as the Bingham Canyon mine in Utah, often recover c

3. By gold panning equipment on Jul 15, 2009 | Reply

   In the early days of any gold rush, miners go to the creeks and pan for gold. They get a shovelful of gravel/sand and throw it in their mining pan and swish it with water. The heavy gold falls to the bottom as the gravel is washed away.

   Then within a short time two or three miners would get together and build a sluice box or rocker – this is just like panning except it’s a long shoot with little boards nailed to the bottom – looks like a chicken ladder. As the gravel and sand is washed down the sluice, the miner rocks the sluice box and the gold settles out behind the little boards in the “chicken ladder”.

   These low-tech ways of getting gold out of the creek are always the first techniques to be used. But all the time time the miners are looking around for the source of the gold which is in the creek – when they find that, then they begin mining through hard rock following the “color” in the rock.

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