Mining/Extraction
Gold is extracted from the earth via hard rock mining, alluvial mining, or placer mining. The ore contains gold mixed with rock and other minerals.
7 Main Steps in Gold Processing
Crushing and Grinding
The gold ore is crushed into small pieces and then ground into fine powder to liberate the gold particles from the surrounding rock.
Concentration
Gold is separated from other materials using methods like: Gravity separation (sluicing, panning) Flotation Cyanidation (chemical leaching) Amalgamation (mercury, though it's now discouraged due to toxicity)
Smelting/Melting
The concentrated gold is heated in a furnace at high temperatures to separate the metal from impurities. This produces impure gold doré bars (typically 70-90% pure).
Refining
Refining increases gold purity to 99.5% to 99.99%.
Casting/Bar or Product Forming
The pure gold is cast into gold bars, coins, granules, or prepared for jewelry manufacturing.
Fabrication (Final Stage)
The final stage depends on the end product: 1. Jewelry 2.Bars 3. Industrial Use