It won't fade Placer gold is only gold with impurities, and the purity after elutriation is much lower than that of pure gold. Placer gold is produced at the bottom of the river or in low-lying areas, mixed with stone and sand. After elutriation, the color changes with fineness. More than 90% is red and yellow, 80% is light yellow, and 70% is cyan yellow. The characteristics of placer gold are: the particle size is different, the big one is like broad bean, the small one is like fine sand, and the shape is different.

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Extraction of placer gold:

Placer gold mines use the physical properties of minerals to extract gold without chemical treatment or changing the properties of the original placer gold mine. Therefore, in terms of purity, it is not as high as gold ore.

In order to extract gold from placer gold mine, it is necessary to crush and grind the ore, preconcentrate it through mineral processing or separate gold from the ore. Gravity separation and flotation are common methods for gold mineral processing, and gravity separation plays a very important role in the production of placer gold mineral processing equipment and placer gold mineral processing equipment.

Flotation is a widely used mineral processing method in rock gold mines. At present, about 80% of rock gold deposits in China use this method to select gold. The level of placer gold processing equipment and placer gold beneficiation equipment has been greatly improved. After beneficiation, the ore is crushed, beneficiated and enriched by heavy sand method, and then refined in the furnace.

Baidu encyclopedia-placer gold (ore)