How Gold is Produced
This chart illustrates the general steps in open-pit gold mining. The specifics of the process vary from mine to mine.
1. Geologists use the latest technology, such as satellite surveys and geochemistry, to locate an ore deposit.
2. Computers are used to design the mine, which requires precise and accurate measurement of the ore deposit. Construction begins following the lengthy process of receiving permits.
3.
Samples of ore are examined to determine grade and metallurgical characteristics. Broken rock is marked by type for efficient processing.
4. Based on its metallurgical makeup, a dispatcher directs truck operators to deliver the ore to the correct processing location.
6. The gold is absorbed (collected) out of solution onto activated carbon. The remaining cyanide solution is recycled.
7. 
The gold loaded carbon is moved into a vessel where the gold is chemically stripped from the carbon which is then recycled.
8. 
Gold is precipitated from the solution electrolytically or by chemical substitution.
9. The pure gold is then melted into dore’ bars containing up to 90 percent gold. Dore’ bars are then sent to an external refinery to be refined to bars of 999.9 parts per thousand pure gold.
Reclamation is a long-term investment made by every gold mining company, and can cost anywhere from $2,000 to $10,000 per acre. It is the cornerstone of every mine plan and is considered the first and last step of the mining process.
Gold is produced at some mines as part of the process of mining and refining other metals, such as copper. At those operations, gold is refined to an acceptable purity as part of the copper production process. At most gold mines, the gold “dore” is sent to a refinery for further processing.
Tags: Environment, Gold, Mining