The North American Kwakiutl Indians acquired the skill of melting metal at a relatively early stage. They poured large plates of metal which were invested with both magical and economic powers. The value of the individual plates was determined by the number of rituals in which they were involved. According to the Kwakiutl, all matter has a soul. If a metal plate broke, you could hear its soul. They warmed the souls by wrapping the plates in a cloth. The plates, broken into fragments, circulated as a means of exchange. It was important to make sure that the fragments returned to their place of origin, where they were welded together again.