Pennyweight is derived from the price for a hundred nails in 15th century England: the larger the nail, the higher the cost per hundred. The pennyweight also bears no relation to the weight of the American "penny" (1 cent) coin, which weighs 2.5 g (for those minted after 1982). Pennyweight A pennyweight (abbreviated dwt, from denarius weight) is a unit of mass that is equal to 24 grains, of a troy ounce, of a troy pound, approximately 0.054857 avoirdupois ounce and exactly 1.55517384 grams. In the Middle Ages, a British penny's weight was literally, as well as monetarily, of an ounce
Five Grains categories of grains. The name is typically translated as the "Five Grains" or the "Five Portions of cereal", and less often as the "Five Sacred Grains" or "Crops". Some context is important to understanding the concept, however. First, this use of "five" predates modern botanical notions and is better understood as part of the symbolic use of numbers in Chinese culture. From a very early date, Han culture understood the world as composed of five elements and many corresponding pentads were enumerated, including the Five Directions (south, north, west, east, "and" center), the Five Colors (red, black, white, "qing", and