Coins can be made in three different ways: casting from moulds; striking by hand; and using machinery. Casting techniques were generally limited to the earliest issues, except in East Asia. Hand
production involved placing hot metal blanks between two engraved dies, and hammering them together to produce two-sided coins. In the West, mechanised production began in the 16th century, but the tremendous scientific and industrial progress of the 18th and 19th centuries, with the introduction of steam power, revolutionised coin production. The 21st century mint is almost fully automated, including computer software and computer-aided manufacture for designing and cutting dies.
Answered by Keith Sugden, Manchester Museum.