The scientific name for cowries is Cypraea. The word cowrie comes from the Hindu Kauri, while Cypraea comes from the latin word Cypraes, the Island of Cyprus where metal for coins was mined. Both names probably are related to two species in particular, the money Cowrie, Cypraea moneta and the ringed cowrie, Cypraea annulus. Both of these cowries are included in the shell set. These two shells were widely used as money before metal coins. In fact, the first metal coins in the Classical World were minted in the shape of cowries. In the Orient, cowrie usage was very ancient. Cowries were buried in Neolithic and Shang tombs in China over 3,500 years ago. In the Han period of China, pottery drums were made for storing money cowries. In Africa, the use of cowries as money persisted much longer, and in the 18th century, 20,000 money cowries could buy a bride in certain times. Man has long admired the shiny cowrie. In primitive cultures, these shells have a ritualistic, mystical significance often representing the female in fertility cults. In Fiji, a cowrie is the badge of nobility. In the mediterranean world, cowries were called porcellana, which means "little female pig", presumably referring to the curved pig-like back of the little white shells. When Chinese porcelain first reached the West, the texture and luster of glazed porcelain was reminiscent of only one thing: the shiny surface of the cowrie. This is the origin of our modern word for porcelain. This admiration was also demonstrated by naming certain cowries after precious metals: the onyx cowrie, Cypraea onyx and the carnelian cowrie, Cypraea carneola are examples. Today cowries are prized mainly among shell collectors. Cowries are popular with collectors because of their sheen and intricate designs. Generally spots or bands predominate but there are many other patterns that exist as well. They are often sold in Hawaii as souvenirs with the outer shell engraved. Living cowries are shy nocturnal creatures that live only in tropical marine waters and hide under rocks or coral during the day. They are generally herbivores, feeding on plant-life. Young cowries build their shells in a narrow spiral shape. This inner shell gradually becomes enclosed by a larger outer shell, as the cowrie matures. The uter shell has the typical oval shape that we recognize as a cowrie shell. When a damaged shell is found, the inner spiral structure can be seen through the outer layer.