On stand – gold – Obsidian

Obsidian is a volcanic glass that occurs in all sorts of colours. It is a kind of stone that has been used since the dawn of man to make tools and weapons. It is a very useful material, because the edge can be as thin as one molecule. For that reason people still use it to make precision scalpels. A lot of Meso-American cultures used Obsidian for tools, but also jewellery, because of the great abundance of Obsidian in volcanic areas of America. The Ancient Greeks used the volcanic glass as mirrors. Obsidian forms when most of the gasses and the water has evaporated from the lava. That causes the lava to become very thick, which prevents crystallisation. That means most of the Obsidian becomes amorphous, except for crystallised inclusions in the volcanic glass. Sometimes, synthetic, brightly-coloured glass is sold as obsidian, but this is not a natural variety.