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
Bullion precious metals. Bullion Bullion is gold, silver, or other precious metals in the form of bars or ingots. Typically, bullion is used for trade on a market. The word "bullion" comes from the old French word "bouillon", which meant "boiling", and was the term for the activity of a melting house. The value of bullion is typically determined by the value of its precious metals content, which is defined by its purity and mass. To assess the purity of gold bullion, the centuries-old technique of fire assay is still employed, together with modern spectroscopic instrumentation, to accurately determine its quality