The extremely low content of gold in the ore, in order to obtain gold ore crushing and grinding needs to be dressing method and selection of pre enrichment or the gold from ore separation. More use of gold in ore dressing is gravity separation and flotation, gravity separation position is very important in placer gold production occupies, flotation is rock gold mine for ore dressing methods used widely, at present about 80% of China's rock gold mine choose this method of gold selection, processing technology and equipment have greatly improved.

(a) crushing and grinding

According to the query, the Chinese gold selects the jaw of rough crusher, use of standard cone crusher crushing and fine crushing, selection of short head cone crusher and roll crusher. Middle and small gold mostly choose a closed-circuit crushing two large gold three selection of a closed-circuit crushing process.

In order to improve mineral production capacity, tap the potential of equipment for crushing process was modified and the grinding machine utilization factor increased, the main measures adopted is the implementation of more crushing and less grinding, reduce the particle size of ore into the mill.

(two) gravity

Gravity are widely used in rock gold mines, much as assistive technology, recovery of coarse gold in grinding circuit, flotation and cyanidation technology to create favorable conditions, improve mineral processing targets, improve the total recovery of gold, to increase output and played a positive effect to reduce the cost. There are about more than 10 gold selected re-election this technology in Shandong Province, the average total recovery can be increased from 2% to 3%, good economic efficiency of enterprises, according to incomplete statistics, a year can have hundreds of million profit. Henan, Hunan, Inner Mongolia and other provinces (area) also achieved good results, the main equipment selection chute, shaker, jig and short cone cyclone etc.. In China most of the gold mines, flotation combined gravity flow (flotation tailings by gravity) suitable for selection, should vigorously promote back stage grinding and stage separation process can be advocated, early harvest beneficiation principles.

(three) flotation