Cross reference
Exodus 25:3
3 And this is the offering which ye shall take of them: gold, and silver, and brass,
Deuteronomy 8:9
9 a land wherein thou shalt eat bread without scarceness, thou shalt not lack anything in it; a land whose stones are iron, and out of whose hills thou mayest dig copper.
Job 28:2
2 Iron is taken out of the earth, And copper is molten out of the stone.