From BiblePortal Wikipedia

Smith's Bible Dictionary [1]

Mining. A highly-poetical description given by the author of the book of Job of the operations of mining as known in his day is the only record of the kind which we inherit from the ancient Hebrews.  Job 28:1-11. In the Wady Magharah , "the valley of the cave", are still traces of the Egyptian colony of miners who settled there for the purpose of extracting copper from the freestone rocks, and left their hieroglyphic inscriptions upon the face of the cliff. The ancient furnaces are still to be seen, and on the coast of the Red Sea are found the piers and wharves, whence, the miners shipped their metal in the harbor of Abu Zelimeh.

Three methods were employed for refining gold and silver:

(1) by exposing the fused metal to a current of air;

(2) by keeping the alloy in a state of fusion and throwing nitre upon it; and

(3) by mixing the alloy with lead, exposing the whole to fusion upon a vessel of bone-ashes or earth, and blowing upon it with bellows or other blast. There seems to be reference to the latter in  Psalms 12:6;  Jeremiah 6:28-30;  Ezekiel 22:18-22.

The chief supply of silver in the ancient world appears to have been brought from Spain. The Egyptians evidently possessed the art of working bronze in great perfection at a very early time, and much of the knowledge of metals which the Israelites had must have been acquired, during their residence among them. Of tin, there appears to have been no trace in Palestine. The hills of Palestine are rich in iron, and the mines are still worked there, though in a very simple, crude manner.

Webster's Dictionary [2]

(1): ( a.) Of or pertaining to mines; as, mining engineer; mining machinery; a mining region.

(2): ( v. i.) The act or business of making mines or of working them.

(3): ( p. pr. & vb. n.) of Mine