Editing Blacksmith (section)

=== Before the Iron Age ===
[[Gold]], [[silver]], and [[copper]] all occur in nature in their [[native state]]s, as reasonably pure metals{{snd}} [[humans]] probably worked these metals first. These metals are all quite [[malleable]], and humans' initial development of hammering techniques was undoubtedly applied to these metals.

During the [[Chalcolithic]] era and the [[Bronze Age]], humans in the Mideast learned how to [[smelting|smelt]], [[Melting|melt]], [[Casting (metalworking)|cast]], [[rivet]], and (to a limited extent) [[forge]] copper and bronze. Bronze is an [[alloy]] of copper and approximately 10% to 20% [[Tin]]. Bronze is superior to just copper, by being harder, being more resistant to corrosion, and by having a lower melting point (thereby requiring less fuel to melt and cast). Much of the copper used by the Mediterranean World came from the island of [[Cyprus]]. Most of the tin came from the [[Cornwall]] region of the island of [[Great Britain]], transported by sea-borne [[Phoenicia]]n and [[Greeks|Greek]] traders.

Copper and bronze cannot be hardened by heat-treatment, they can only be hardened by [[cold forming|cold working]]. To accomplish this, a piece of bronze is lightly hammered for a long period of time. The localized stress-cycling causes [[work hardening]] by changing the size and shape of the metal's [[crystallite|crystals]]. The hardened bronze can then be ground to sharpen it to make edged tools.

[[Clockmaker|Clocksmiths]] as recently as the 19th century used [[work hardening]] techniques to harden the teeth of [[brass]] [[gear]]s and [[Ratchet (device)|ratchets]]. Tapping on just the teeth produced harder teeth, with superior wear-resistance. By contrast, the rest of the gear was left in a softer and tougher state, more capable of resisting cracking.

Bronze is sufficiently corrosion-resistant that [[Artifact (archaeology)|artifacts]] of bronze may last thousands of years relatively unscathed. Accordingly, museums frequently preserve more examples of Bronze Age metal-work than examples of artifacts from the much younger [[Iron Age]]. Buried iron artifacts may completely [[rust]] away in less than 100 years. Examples of ancient iron work still extant are very much the exception to the norm.