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International Colored Gemstone Association

European Ruby Conference

Agreement Relating to the Establishment of a Reserve of Industrial Diamonds Upon the North American Continent

Convention on the Control and Marking of Articles of Precious Metals

Convention Relating to the Unification of Excise Duties and of Fees for the Warranty of Articles of Precious Metals

Comité de l'industrie diamantaire pour le Marché commun

European Gemmological Laboratory

Gem and Jewelry Education Organization

International Gem Finders Society

International Turquoise Association