Besides a double necklace and ear-rings of a woman, many articles made of obsidian, a volcanic product sometimes called volcanic glass, have been found in Therasia. These are cut, but not polished; some of a triangular form have probably been the points of arrows; others are like small knives or scrapers for preparing skins. The use of obsidian appears to have been common during the Stone age among those nations who lived in volcanic regions, and even in later periods. It is said that it is still used by the women of Peru for scissors. It was more generally in vogue before the discovery of metals than since, particularly in Greece, where arms and tools of stone disappeared after copper was found. In the strata where they are at Therasia, there is nothing of iron or bronze. Two small rings of gold are rather remarkable; they are so small that they would not pass over a child's finger. It may be inferred that they were links of a necklace. In each there is a hole about the size of a needle's eye. Probably they had been threaded one after another on the same string, and not interlaced like the rings of a chain. The interior is hollow; and no indication of soldering can be perceived, neither does the gold seem to have any alloy of other metal. The maker had flattened the bit of native gold by hammering it to the state of a thin circular leaf, and then folding it up with the edges to the inside of the ring. As gold has never been found in Santorini or in any of the neighbouring volcanic islands, it proves that the inhabitants held communication with the continent; certain streams of Asia Minor having been celebrated in antiquity for the great quantity of gold brought down.