Gravity concentration has been historically the most important way of extracting the native metal using pans or washing tables However froth flotation processes may also be used to concentrate the gold In some cases particularly when the gold is present in the ore as discrete coarse particles a gravity concentrate can be directly smelted to form gold bars In other cases particularly when the gold is present in the ore as fine particles or is not sufficiently liberated from the host rock the concentrates are treated with cyanide salts a process known as cyanidation leaching followed by recovery from the leach solution Recovery from solution typically involves adsorption on activated carbon followed by solution concentration or stripping and or electrowinning. Froth flotation is usually applied when the gold present in an ore is closely associated with sulfide minerals such as pyrite or arsenopyrite and when such sulfides are present in large quantities in the ore In this case concentration of the sulfides results in concentration of gold values Generally recovery of the gold from the sulfide concentrates requires further processing usually by roasting or wet pressure oxidation These pyrometallurgical or hydrometallurgical treatments are themselves usually followed by cyanidation and carbon adsorption techniques for final recovery of the gold

Sometimes gold is present as a minor constituent in a base metal (eg copper) concentrate and is recovered as a by-product during production of the base metal For example it can be recovered in the anode slime during the electrorefining process “Gold extraction” or recovery from its ores may require a combination of comminution mineral processing processes to be performed on the ore at a placer mine in Dutch Flat California sometime between 1857 and 1870Gold mining from alluvium ores was once achieved by techniques associated with placer mining such as simple gold panning and sluicing resulting in direct recovery of small gold nuggets and flakes Placer mining techniques in the present day are the practice of artisan miners Hydraulic mining was used widely in the Californian gold rush and involved breaking down alluvial deposits with high-pressure jets of water Hard rock ores form the basis of the majority of commercial gold recovery operations today and are mined using open pit or sub-surface mining techniques.

The Gold Washing Machine is made up of cutter suction processing equipment and sluice type gold processing equipment, compound type gold processing sluice is the most advanced and large production grain selection equipment in the world. Complete upland alluvial gold extraction equipment are introduced; This set of equipment is one of our leading products with many years of production history, exported to west Africa, central Africa, Indonesia, Philippines, Nepal, north Korea, Canada and other countries and the major domestic mines. This equipment has features: Basic requirement is simple, easy installation, convenient to move, to the mine environment and facilities requirements low.

Well suited for scalping and screen applications, the vibrating grizzly feeder manufactured by Hongxing Machinery is ideal for removing oversized rock and separating fines from crusher feed. Hongxing Machinery’s ruggedly designed and constructed frame lowers maintenance costs, insuring continuous operation and longer overall product life. The VGF provides superior material separation and adaptability for different products and specifications.

Vibrating type screening machine is the circular vibrating type. With adjustable amplitude, multi-layers and long screening line and this kind of screen can work more efficiently. The vibrating screen is a kind of sieving equipment of international advanced level, developed by our company on the basis of carrying on the advantages of traditional screens and absorbing the outstanding technology from abroad. Application area: metallurgy, coal mining, mining-selecting, building, chemistry. The screening material: limestone, gypsum, talcum, calcite, bauxite, granite etc. Main components: screen meshes, spring, and support frame Working principle: the rotating changes into vibration through the vibrator, which causes materials slip on the screen to be sieved.