The term milled coinage is used to describe coins which are produced by some form of machine, rather than by manually hammering coin blanks between two dies (hammered coinage) or casting coins from dies.
The earliest machine known for producing coins is the screw press, believed to have been invented by Leonardo da Vinci in the 15th century.
The earliest milled coins produced in England date from the early 1560s, but a milled coinage did not entirely replace the hammered coinage until 1662.
