Coins of the pound sterling another silver coin, the sceat, of 20 troy grains weight, which was in general circulation in Europe during the Middle Ages. The weight of the English penny was fixed at troy grains (about 1.46 grams) by Offa of Mercia, an 8th-century contemporary of Charlemagne. The coin's designated value, however, was that of 24 troy grains of silver (one pennyweight, or of a troy pound, or about 1.56 grams), with the difference being a premium attached by virtue of the minting into coins. Thus, 240 pennyweights made one troy pound of silver in weight, and the monetary value of 240 pennies
Penny (English coin) modern grains (1.3 to 1.5 g). It was standardized to 32 Tower grains, 1/240th of a Tower pound (approx. 350 g). The alloy was set to sterling silver of 925/1000 in 1158 under King Henry II. The weight standard was changed to the Troy pound (373.242 g) in 1527 under Henry VIII, i.e. a pennyweight became about 1.555 grams. As the purity and weight of the coin was critical, the name of the moneyer who manufactured the coin, and at which mint, often appeared on the reverse side of the coin. From the time of King Offa, the penny was