Minting Technologies
Coins were first made of scraps of Copper. modern coins were produced through a process of hitting a hammer positioned over an anvil. The Chinese produced primarily cast coinage, and this spread to South-East Asia and Japan. Relatively few non-Chinese cast coins were produced by governments, however it was a common practice amongst counterfeiters. Since the early 18th century and before, presses (normally referred to as mills in coin collecting circles) have been used in the west, beginning with screw presses and progressing in the 19th century towards steam driven presses. The first of these presses were developed in France and Germany, and quickly spreading to Britain. Recently modern minting techniques involving electric and hydraulic presses have been more commonly employed.
The type of mintage method (being hammered, milled or cast) does limit the materials which can be used for the coin. For example antimony coins, (which are very rare) are nearly always cast examples, because of the brittle nature of the metal, and thus it would break if deformed, which is a key part of the milling or hammering process.
Read more about this topic: History Of Coins