Imperial and US customary measurement systems the Troy units of weight—the troy ounce used to this day for weighting precious metals. Edward I (1272–1307) broke the link between a coin's value and its weight when he debased the English coinage by introducing a groat (four pence) which weighed of 89 grains rather than the expected 96 grains. The groat was further devalued in the 1350s when its weight was reduced to 72 grains. During Saxon times land was measured both in terms of its economic value and in terms of its size. The Domesday Book used the hide, an economic unit of measure. In other references
Hong Kong units of measurement and the inch or "tsun" (). Chinese, Imperial and metric weight units are all used in Hong Kong. The choice of system depends on the type of goods and their origins. Metric is used for all official purposes, for example the Post Office and Road signs. Packaged food weights and volumes may be given using any of the three systems of units. Traditional weights are still "de facto" standard in certain areas. For example, vegetables, meats, and Chinese medicines are usually measured in Chinese units, while some fruits are normally measured using the Imperial system. Precious metals (gold, silver and