The metalsmith has a very old pedigree. Cain was a smith, and it was one of his descendants, Tubal-Cain, who was described as “the forger of instruments of bronze and iron” (Genesis 4:17,22). Cain was the father of the Midianite tribe of Kenites who seem to have been involved in many aspects of Israel’s history (see, for example Genesis 15:19; 1 Samuel 15:6). They appear to have exploited the copper of the Sinai with the Egyptians. Artifacts of Kenite metalworking have yielded much of the archaeological information we know concerning ancient metal-working.
Gold was one of the first metals to be extracted and used because it is found in a relatively pure state and can be melted at low temperatures and poured into Moulds. It was refined (like silver) by heating it in a clay crucible and skimming the top of the liquid to remove impurities (Zechariah 13:9). It was also beaten into thin sheets were cut into strips fine enough to be woven into gold thread (Exodus 39:3).
Israelite are and craft was at its best in many small objects such as jewelry, and the goldsmiths were therefore important as a group (Nehemiah 3:8). Cooper was extracted from its ore by heating. It could be beaten and shaped by cold hammering. It was mined from shafts as much as one hundred and fifty feet (fifty metres) deep, and the description of mining given in Job 28:2-11 seems to have been written from some experience. The ore was broken down to small pieces in stone mortars and smelted in a simple furnace fired by acacia wood. The furnace consisted basically of a depression in the ground where the copper ingot would ultimately be collected, surrounded by three low walls of stone and clay. The third side gave access to a bellows and to the prevailing wind.
Remains of mortars, furnaces, and slag heaps are to be found in plenty along the Gulf of Aqaba. By 2000 BC metal workers had discovered that by adding up to four percent of tin to the copper, they obtained a harder metal with a lower melting-point which could be poured into moulds. This was bronze. In the Hebrew language there is no distinction between bronze and copper.
Because bronze was attractive and cheaper than gold it was sometimes used as a decorative substitute (see 1 Kings 14:27). The copper industry died out in the south because of the lack of fuel; the acacia trees were all burned up. There was no revival of the industry in the country until Roman times.
Iron was originally removed as an impurity from copper. It was not until certain technological advances had been made that iron could be extracted from its ore. It required more heat both for extraction and for shaping (Isaiah 44:12; Jeremiah 6:28-29). The Hittites developed iron first and exported it and the related skills to the Canaanites and the Philistines.
Since iron was much stronger than bronze, and the Canaanites had iron fittings to their chariots (Judges 1:19), the Jews had problems in battle. At a later period, the Philistines. who were not great in numerical strength, were able to dominate the Jews because of their monopoly of iron (1 Samuel 13:19-20). In 1500 BC iron was so new that it was being used to make jewelry, but by 1000 BC it was being used in weapons. David had plenty of iron to provide construction materials for the Temple (1 Chronicles 22:3).