Tourmaline |
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This semi-precious stone, a coloured variety of chalcedony, features facets with different shades. The agate used to be extracted in India, Egypt and Germany. Today it is found in Brazil and Uruguay. In 18th century France, the agate was used in the Ille-et-Vilaine region in West of France for jewel manufacturing purposes. Since then this stone has also been applied to industrial processes. These stone varieties exhibit a milky transparency and some of them are indeed precious: cornelian (red) ; chrysoprase (light green) ; agate ; neliotrope (dark green with red spots). |
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