Apothecaries' system between actual and nominal weight. In the 19th century, most European countries or cities still had at least a "commercial" or "civil" system (such as the English avoirdupois system) for general trading, and a second system (such as the troy system) for precious metals such as gold and silver. The system for precious metals was usually divided in a different way from the commercial system, often using special units such as the carat. More significantly, it was often based on different weight standards. The apothecaries' system often used the same ounces as the precious metals system, although even then the
Texas Precious Metals Metals (NASDAQ: AMRK), a publicly traded precious metals wholesaler, to manufacture and distribute Texas Mint products to dealers throughout the United States. In 2014, Texas Precious Metals and the Perth Mint of Australia released the Houston-Perth "Sister Cities" coin, commemorating the strong ties between the cities' energy sectors. The half-ounce, 99.9% pure silver coin features offshore and onshore oil rigs showcasing the cities' historic energy sectors. The coin also pays homage to the flags of Texas and Australia. The coin measures 32mm in diameter with a thickness of 2mm, and has a legal tender face value of AUD$0.50. The coins