As the old saying goes: when a thing is rare, it becomes precious. Therefore, since ancient times gold was regarded as the first of hardware, and its eternal reputation is unmatched by other metals. Gold is dense, soft, shiny and the most malleable and ductile pure metal known. Pure gold has a bright yellow color and luster traditionally considered attractive, which it maintains without rusting in air or water.
The significant application of gold
As a highly sought-after precious metal in jewelry, sculpture and ornamentation since the beginning of recorded history, gold obviously has an irreplaceable position in metal category.
Gold readily creates alloys with many other metals. These alloys can be produced to modify the hardness and other metallurgical properties, to control melting point or to create exotic colors. Gold is a good conductor of heat and electricity and reflects infra red radiation strongly. Chemically, it is unaffected by air, moisture and most corrosive reagents, and is therefore well-suited for use in coins and jewelry and as a protective coating on other, more reactive, metals.
Gold ore beneficiation process
Gold ore beneficiation process can be divided into the following steps:
Crushing is often divided into three stages, namely, primary crushing, secondary crushing and fine crushing. To complete primary crushing, people usually use a jaw crusher or impact crusher. jaw crusher is used in primary crushing station. It can crush gold ore into smaller sizes. Thus, these small gold ore can be fed into mill such as ball mill for grinding. Impact crusher is generally used after jaw crusher, and can crush hard stones, not only the gold ore, but also other ores such as copper, bauxite, tin, Kaolinite, manganese etc.
Secondary crushing: after reaching certain size, the materials can be fed to grinding mills for further grinding. Commonly used grinding mills are ball mill, vertical roller mill, high pressure suspension grinding mill, MTM medium speed trapezium mill and SCM series super thin mill.
After grinding by a ball mill, the gold ore fines are fed into spiral classifier. By the principle of different solid particles have different sedimentation rate in liquid, spiral classifier washing the mixture of ore and grading them.
After washing and grading, mineral mixture were fed into the magnetic separation. Due to the different susceptibility of various minerals, magnetic and mechanical force can separate the magnetic material from the mixture materials.
Flotation separation: The process used to separate gold and metal sulfides from the gangue. Aeration of the milled slurry, and the addition of specific chemical reagents, encourages froth formation, while activators are added to promote flotation of gold-bearing compounds. The froth that floats to the surface contains most of the gold and iron sulfides, and is extracted for further treatment. This material is known as the concentrate. After magnetic separating, minerals particles were sent to the flotation separation. Now, put into different chemicals according to mineral characteristics, so you can make the minerals and other substances to be separated .