The mineralized rock at Donlin Gold would require multiple steps in processing to extract the gold.

1. Mineralized rock is first crushed, then ground in large mills to create a fine, silt-like powder.
2. The gold-bearing minerals are then separated from other materials using a process called “flotation.”
3. A process called “pressure oxidation” is used to oxidize the gold-bearing materials.
4. The oxidized material is mixed with a cyanide solution in large tanks inside the mill. The gold dissolves in the cyanide.
5. The dissolved gold is then collected onto activated carbon, and the cyanide solution is sent to a cyanide-detox unit. Any trace amounts of cyanide left in the tailings would break down further under natural conditions.
6. The gold is then extracted from the carbon and refined into doré bars.