but this required costly, deep mines to be sunk, such as that at Savuka in Witwatersrand which is almost 4kml21;in miles deep. In recent years, mining companies have begun towork deposits nearer the surface with opencast mines in places such as China, Russia and Australia. The Grasberg gold mine in Indonesia is now the world's largest. Most gold is still used for jewellery, but the electronics industry is consuming increasing amounts for use in computer and communications technologies.