Pounds & Pence: U.K Currency

As a unit of currency, the term pound originates from the value of one pound weight of high purity silver known as sterling silver. 
Sterling silver is an alloy of silver containing 92.5% pure silver and 7.5% other metals, usually copper. 
The word sterling is believed to come from the Old Norman French esterlin (meaning little star) transformed in stiere in Old English (strong, firm, immovable).

Coins of Knights Templar France

The U.K currency sign is the pound sign, originally ₤ with two cross-bars, later £ with a single cross-bar. 
The abbreviation comes from librae, solidi, denarii (libra was the basic Roman unit of weight; the solidus and denarius were Roman coins). 

The Caesar´s Denarius

If an amount of money consists only of pence, we put the letter 'p' after the figures. 
For example: 20p is often pronounced "twenty pee" instead of "twenty pence". 
The singular of pence is "penny".