Job 28:2

Iron is taken out of the earth, and brass is molten out of the stone.

Brass - i:e., copper; because brass is a mixed metal of copper and zinc, of modern invention. Iron is less easily discovered and worked than copper: therefore copper was in common use long before iron. Copper-stone is called 'cadmia' by Pliny ('Natural History,' 34:1; 36:21). Iron is fitly said to be taken out of the "earth" (dust), for ore looks like mere earth.