obsidian

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Black or dark-coloured glassy volcanic rock, chemically similar to granite, but formed by cooling rapidly on the Earth's surface at low pressure.

The glassy texture is the result of rapid cooling, which inhibits the growth of crystals. Obsidian was valued by the early civilizations of Mexico for making sharp-edged tools and ceremonial sculptures.

Blue stands for the Pacific Ocean. The yellow stripe represents the Equator. The points of the star symbolize the island's 12 original tribes. Effective date: 31 January 1968. >>