Coins have always been designed with weight in mind. The Roman denarius was a fixed mass of silver, bearing the image of the Emperor on one side. Clipping, the removal of a sliver of metal from the edge of a coin, was a crime of such great temptation and with such great reward that it became a pandemic in the Roman Empire. In the third century AD the amount of silver in the denarius had fallen to almost zero, causing prices to sky rocket throughout the empire. The only way to detect such fraud was with a balance scale, but such a tool was not in the possession of everyone.
Sir Isaac Newton was another who understood the power of the balance scale to uncover fraud. As Master of the Mint from 1696 until his death in 1727 Newton was a zealous persecutor of clippers. He attended the hangings of clippers, recruited informers and spent hours scrutinizing suspicious coins on his balance scale. It was Newton who first put a milled edge on coins. He had the edges of new coins cut with fine, sharp raised lines. The edges of any coins that had been clipped would not have raised edges and would therefore be obvious. Coin auctioneers and collectors today use the same method to check the integrity of coins before they even bother to take them out of their cases and examine them under a magnifying glass. A coin that appears to be genuine under a loupe but is found to be a few hundredths of a gram light will always be found to have been clipped at some time.
Today, in the rarefied world of the coin auctioneer and the serious collector, the scales are consulted before the magnifying glass is taken down from the shelf. It is not sufficient for a coin to read correctly when viewed through the loupe of the suspect coin expert; it must also weigh correctly.
