One of the oldest English weight systems was based on the 12-ounce troy pound—the basis by which coins were minted, and gold and silver weighed for trade and commerce. (The troy pound equaled 5,760 grains, and thus, in ounces, was 5,760/12 or 480 grains; twenty pennies weighed an ounce, and thus, a pennyweight equaled 480/20 or 24 grains.) The troy pound—and the entire system of connected weights— was used until the nineteenth century, mostly by jewelers and druggists. One holdover of the troy ounce (a portion of the troy pound) is found in today’s pharmaceutical market to measure certain drugs—and even in the financial market, as the measurement used to interpret gold and silver prices.