Agate is a semi-precious stone siliceous semi-pellucid compound mineral, consisting of bands or layers of various colours blended together, the base generally being chalcedony, and this mixed with variable proportions of jasper, amethyst, quartz, opal, heliotrope, and carnelian. The varying manner in which these materials are arranged causes the agate when polished to assume some characteristic appearances, and thus certain varieties are distinguished, as the ribbon agate, the fortification agate, the zone agate, the star agate, the moss agate, the clouded agate, etc. In Scotland they are cut and polished under the name of Scottish pebbles. Research Agate
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Abbreviations
Rocks & Minerals
Research Agate
