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Fausset's Bible Dictionary [1]

(See Metals .) Job ( Job 28:1-11) graphically describes mining operations in his times. "He (man) setteth an end to darkness" by exploring with torches the darkest depths, "and searcheth out all perfection the stones of darkness," rather "searches out to the utmost perfection the stones of (embedded in) darkness," i.e. in the dark earth. Three mining hardships follow:

(1) "the flood breaketh out from the inhabitant," a stream breaks out at the side of the strange new comer, namely, the miner; but Gesenius, "a shaft (gully-like pit) is broken open far from the inhabitant" of the earth.

(2) "Forgotten (unsupported) by the foot they hang" (not as KJV "they are dried up,"), namely, by ropes; "far away from men they move with uncertain steps," literally, they stagger. "As for the earth's surface, out of it cometh bread" by tillage; "while under it fire (i.e. stones glowing like fire,  Ezekiel 28:14) is turned up"; Umbreit, "it is turned up by fire" used in mining; Maurer, "as it were by fire." "There is a path which no fowl (eagle) knoweth," i.e. the miner penetrates where the birds of keenest sight cannot see, he ventures where the daring "lion's whelps tread not" after their prey. "He puts forth his hand (to cleave) the flint rock." "He cuts channels among the rocks" to drain off the waters, then "his eye seeth every precious thing." "He restrains the streams from weeping"; poetically for the trickling rills, which hinder mining.

Relics of most ancient Egyptian copper mines are found in the peninsula of Sinai, at the wady Magharah, "the valley of the cave." Hieroglyphic inscriptions remain on the freestone cliff from whence the Egyptian colony extracted copper. Under Manetho's fourth dynasty, which erected the great pyramid of Gizeh, copper mines were worked by a colony (Lepsius). In the Magharah tablets the cartouche of Suphis the builder of the great pyramid is supposed to be read. Opposite Magharah is a fortress with terraces like pyramid steps, supposed to be for the protection of the miners. Hammers of green porphyry within, and reservoirs for water, are found. Ancient furnaces remain; and near the Red Sea piers for shipping the metal at Abu Zelimeh. In the granite mountains E. of wady Mokatteb mines are found; and smelting furnaces and slag in the wady Nasb. Remains of the miners' huts are at Surabit el Khadim. The quartz was broken very fine and ground to powder in mills, to separate the gold from the stone and earth.

To refine it, the cupelling process with lead fused with the gold, the whole being blown upon with the bellows, was employed ( Psalms 12:6;  Jeremiah 6:28-30;  Ezekiel 22:18-22). In  Malachi 3:2-3, "He shall sit as a refiner of silver," the allusion is to the refiner sitting to watch the orange color of the melting alloy upon the cupell becoming gradually lighter in appearance until it entirely passes away, and he sees his image reflected in the glowing mass as in a highlypolished mirror; until then he adds more lead and applies the bellows to blow upon it; but when he is satisfied he removes the metal from the furnace. So, the Lord in purifying His elect ( Romans 8:29;  Job 23:10;  Psalms 66:10;  Proverbs 17:8;  Isaiah 27:8;  Isaiah 48:10) keeps therein the furnace only until they reflect His image ( Hebrews 12:10;  1 Peter 1:7).

He sits to His work, not perfunctorily, but with patient love and unflinching justice. He adjusts the fires intensity and duration with nicest adaptation to His child's spiritual need ( 1 Corinthians 10:13). Tartessus of Spain was near the silver mountain Orospeda, where the metal workers had the art of "spreading silver into plates" ( Jeremiah 10:9). In  Proverbs 17:3, "the fining pot for silver, and the furnace for gold," etc., the sense is, men can test and purify silver in the crucible, and gold in the furnace, but the hearts Jehovah (alone) trieth. Sulphuric acid now is used to part silver from gold; possibly some such process was then known. How Moses "ground to powder" the gold calf we know not; whether by natron, or tartaric acid, which we employ. High skill at all events is implied in  Deuteronomy 9:21, "very small as dust"; he burnt it in the fire first, and strawed the gold dust on the water and made the Israelites drink it; illustrating the spiritual principle that sinners must "eat the fruit of their own ways" ( Proverbs 1:31;  Proverbs 14:14;  Proverbs 22:8;  Job 4:8;  Isaiah 3:11;  Jeremiah 2:19;  Jeremiah 6:19).

Tin is mentioned among Midianite spoils; doubtless obtained from Cornwall and Spain through the Phoenicians. Iron abounds in the rocks of the Holy Land; the Hebrew probably acquired in the Egyptian iron furnaces the art of working it, by some such process as the Indians used from the earliest times ( Deuteronomy 4:20). The speedy decomposition of iron accounts for our not finding Egyptian iron weapons of the earliest times. The difficulty of smelting iron, and the intense heat required, would cause bronze to be preferred, whenever it sufficiently answered the purpose required. Herodotus mentions iron tools as used in building the pyramids. Iron and copper mines of old times are found in the Egyptian desert, and on the tombs about Memphis butchers are depicted sharpening their knives on blue bars of steel.

Smith's Bible Dictionary [2]

Mines. See Mining .