Coin production in England was tightly regulated through contracts between the Crown and the  master-workers of the Royal Mint. Bullion was turned over to the mint by Royal authorities or purchased from individuals and then converted into coinage, which was then issued minus fees for the cost of minting and the King’s seigniorage. In order to assure quality and purity, samples 
were taken from every batch of coins and set aside to be tested at an annual “trial of the pyx.” To assist in identifying the coins, a “privy-mark” (what we call a mint mark) was incorporated that identified the individual responsible for the coin (the moneyer). The mark also helps date it (only a few English coins before 1649 had a date on them). Tracking the moneyer was important since 
the values of the coins were dependent on their metallic content – a shilling was supposed to have had nearly a shilling’s worth of silver in it. If not, the moneyer might face punishment, including execution.

At the beginning of the Civil Wars, almost all English coins were struck by hand (“hammered” coins), except for a few produced by Nicholas Briot, who used rolling presses. During the Commonwealth, steps were taken to begin production of milled coinage and, by 1663, the Royal Mint converted to mechanized coinage once and for all, using screw presses and Peter Blondeau’s secret machinery for creating a high quality, lettered-edge on the coins.

The English Monetary System of Charles I 20 shillings (s) = 1 pound (£) 1 shilling = 12 pence (d) Coin Denominations Gold Triple Unite = 60 shillings Unite = 20 shillings Angel, double crown, 1/2 Unite = 10 shillings Silver Pound = 20 shillings Crown - 5 shillings Half Crown = 2 shillings 6 pence Shilling = 12 pennies Sixpence = 6 pennies Fourpence (groat) = 4 pennies Threepence = 3 pennies Twopence (halfgroat) = 2 pennies Penny = penny Half Penny = 1/2 penny Copper Farthing = 1/4 penny

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