Gold in nature is a natural product that exists in a free state and cannot be synthesized. According to its source of different and refining the content of different into raw gold and cooked gold and so on.
Raw gold is also known as natural gold, barren gold, raw gold, is the object of cooked gold, from the mine or river bottom alluvium mining without melting refining of gold. Raw gold is divided into mine gold and sand gold two kinds.
Mineral gold, also known as alloy gold, produced in the mine, gold mine, mostly with the underground gushing out of the hot spring through the rock of the seam fine and precipitation accumulation, often with quartz sandwiched in the crevices of the rock. Most of the mine gold and other metal companion, which in addition to gold and silver, platinum, zinc and other metals, in other metals before the proposed known as alloy gold. Mineral gold is produced in different mines and contains different components of other metals, therefore, the color varies, generally between 50% and 90%.
Alluvial gold, is produced in the river bottom or low-lying areas, and stone sand mixed together, after elution out of the gold. Alluvial gold originates from mines, is due to the gold ore exposed to the ground, after a long period of wind and rain, the rocks by weathering and crumbling, gold will be out of the vein along with the sediment down the water, natural precipitation in the stone sand, in the river bottom or gravel below the deposit for gold-bearing layer, thus forming alluvial gold. The characteristics of alluvial gold are: particle size varies, large like beans, small like fine sand, the shape varies. The color is different due to the high and low color, more than 90% for the red yellow, eight become light yellow, seven become greenish yellow.
Cooked gold is raw gold after smelting, purification of gold, generally higher purity, fine density, some can be used directly for industrial production. Commonly there are gold bars, gold nuggets, gold ingots and a variety of different jewelry, utensils, gold coins and industrial gold wire, gold flakes, gold plate, etc. Due to different uses, the required color varies, or because there is no purification equipment, and only melted not purified, or the purity of the mention is not enough, the formation of gold of varying color.
People are accustomed to according to the color of high and low cooked gold is divided into pure gold, red gold, color gold 3 kinds.
Gold after purification to reach a fairly high purity of gold called pure gold, generally refers to reach 99.6% above the color of gold.
The meaning of red gold and pure gold is close, but because of the time and place of different, the standard of red gold is different, the international market sold gold, color up to 99.6% is called red gold. The gold sold on the international market is called red gold if it reaches 99.6%. The gold in the country is generally between 99.2% and 99.6%.
Colored gold, also known as "secondary gold", "tide gold", refers to the lower color of gold. This gold due to other metal content is different, into the color of high 99%, low only 30%.
According to contain other metal different division, cooked gold can be divided into clear gold, mixed gold, k gold and so on. Clear gold refers to the gold in only mixed with silver components, regardless of the color is high or low collectively called clear gold. Clear gold is more, commonly in gold bars, ingots, gold and a variety of utensils and gold jewelry.
Mixed color gold refers to gold in addition to containing silver, but also contains copper, zinc, lead, iron and other metals. According to the type and amount of metal contained in different, can be divided into small mixed gold, big mixed gold, bronze big mixed gold, lead containing big mixed gold and so on.
K gold refers to silver, copper according to a certain proportion, in accordance with the formula of full gold for 24k formulated into gold. Generally speaking, k gold contains more silver proportion, the greener colour; contains copper proportion is large, the color is purple red.
