Pound (mass) a legal unit for trade (it was abolished in the United Kingdom on 6 January 1879 by the Weights and Measures Act of 1878), but the troy ounce, of a troy pound, is still used for measurements of gems such as opals, and precious metals such as silver, platinum and particularly gold. The system called Tower weight was the more general name for King Offa's pound. This dates to 757 AD and was based on the silver penny. This in turn was struck over Arabic dirhams (2d). The pound was based on the weight of 120 Arabic silver dirhams, which
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