Commercial

This complete fold-up coin balance is a very rare find from the excavations, reminding us of the importance of commerce in Waterford in the late 12th century. It was used to ensure that a silver penny was the proper weight. 240 pennies weighed or should weigh a pound weight of silver, hence 240 old pence in the pre-decimal (pre-1971) £1.00. Made of two arms and a shaft all of yew wood, with an iron pin, the horizontal arm pivots through a slot in the vertical arm and folds up into the vertical. A coin of proper weight or better would tip up the balance and slide off. When used in a mint, the moneyer could then clip the coin to the proper weight. A coin without the proper amount of silver would not be heavy enough to lift the arm of the balance and would not fall off. Also, although the balance appears to weigh coin against a fixed weight, one can quickly learn how much a coin is underweight by the position at which it will finally tip the scales. Only officials of the mint were allowed to use such balances but although denounced by the church as a sin, they were probably used illegally by merchants who kept a perfect coin against which to check that other pennies they received were not clipped.

Coin-clipping was a well-documented crime in the Middle Ages for which there was a severe punishment. There were mints established in Waterford by John as both prince and king, Edward I and Edward IV, probably in Reginald's Tower. Coins from all these mints are represented in the display on commerce in Reginald's Tower today and an original Waterford Prince John penny is placed in this balance as the coin the owner would have used.