Two pence (British decimal coin) dots, a common feature on coins, known as beading. As with all new decimal currency, until 1984 the portrait of Queen Elizabeth II by Arnold Machin appeared on the obverse, in which the Queen wears the 'Girls of Great Britain and Ireland' Tiara. Between 1985 and 1997 the portrait by Raphael Maklouf was used, in which the Queen wears the George IV State Diadem. In 1992 the metal used in minting this coin was switched from bronze to copper-plated steel. From 1998 to 2015 the portrait by Ian Rank-Broadley was used, again featuring the tiara, with a signature-mark below the
Cocker's Decimal Arithmetick Cocker's Decimal Arithmetick Cocker's Decimal Arithmetick is a grammar school mathematics textbook written by Edward Cocker (1631–1676) and published posthumously by John Hawkins in 1684. "Decimal Arithmetick" along with companion volume, "Cocker's Arithmetick" published in 1677, were used in schools in the United Kingdom for more than 150 years. The concept of decimal fractions and the advantages of using them in calculations were well known, but a wide variety of different notations were in use. After surveying various notations, "Decimal Arithmetick" recommends the decimal point notation introduced by John Napier: "Decimal Arithmetick" gives instructions for calculations involving decimals, methods of