Pennyweight Act of 1878; only the Troy ounce and its decimal subdivisions remained official. The Troy ounce enjoys a specific legal exemption from metrication in the UK. The pennyweight is the common weight used in the valuation and measurement of precious metals. Jewellers use the pennyweight in calculating the amount and cost of precious metals used in fabricating or casting jewellery. Similarly, dentists and dental labs still use the pennyweight as the measure of precious metals in dental crowns and inlays. Pennyweight and grains are still used to weigh gooseberries in competitions in Cheshire, northwest UK. Over the Pennines in Yorkshire
Imperial Metals Corp shared by both countries are developed." Imperial Metals Corp Imperial Metals Corporation known as IMI Imperial Metals Inc until 2002, is a Canadian metals and mining company. Engaging in the acquisition, exploration, development, mining, and production of base and precious metals in North America, the majority of its holdings and operations are in British Columbia. In 2016 the Company produced 119.17 million pounds of copper, 94,930 ounces gold and 330,960 ounces silver from its Mount Polley and Red Chris mines. Imperial has two operating mines in British Columbia, one in southern Nevada, and two exploration stage projects also in British