Major gold finds since 1987 have been Plutonic, Kanowna Belle and Bronzewing. As near-surface oxidised deposits become depleted, continued production depends on treating primary sulphide ores in which the gold is more difficult to recover by cyanidation. This means investment in new mining capacity, often underground rather than by open pit, and more sophisticated methods of treatment. There are now 52 operations in the State with some underground production. The established method of treating sulphide ores is by roasting.
Producers are now under pressure to consider newer, more environmentally acceptable methods.
A major plant which uses the important new bacterial leaching technology was commissioned at an operation at Wiluna in 1993. Another began production at Youanmi in 1994 using Western Australian developed technology for the first time on a commercial scale. The number of underground gold operations in Western Australia is expected to increase from the present figure of 52. The new operations at Mt Magnet, New Celebration, Ora Banda, Big Bell, Youanmi, Paddington and Kundana will involve substantial tonnages. Exploration is expected to continue to concentrate on the Marymia and Jundee greenstone belts, and on the search for orebodies close to existing gold operations throughout the vast Yilgarn Block.