Currency evolved from two basic innovations: the use of counters to assure that shipments arrived with the same goods that were shipped, and later with the use of silver ingots to represent stored value in the form of grain. Both of these developments had occurred by 2000 BC. Originally money was a form of receipting grain stored in temple granaries in Egypt and ancient Mesopotamia. By the late Bronze Age, it is thought that ox-hide shaped ingots of copper, produced in Cyprus may have functioned as a currency. Gradually the store of value became the metal itself: at first silver, then both silver and gold. Metals were mined, weighed, and stamped into coins. This was to assure the individual taking the coin that he was getting a certain known weight of precious metal. Archimedes' principle was that the next link in currency occurred: coins could now be easily tested for their fine weight of metal, and so the value of a coin could be determined, even if it had been shaved, or otherwise tampered with. Greek coins remained the oldest currency in the world until the adoption of the Euro at which point the Pound Sterling replaced it as the oldest currency still in use today. The origins of sterling are in Roman times. The British pound sign came from the Roman letter L from the abbreviation LSD – librae, solidi, denarii – used for the pounds, shillings and pence of the original duodecimal currency system. http://en.wikipedia.org/wiki/Pound_sterling