The International Coloured Gemstone Association, almost universally referred to by its acronym ICA, is the world's principal trade association for the coloured-stone industry. Founded in 1984 in Idar-Oberstein during the World Coloured Stone Congress, ICA brings together miners, cutters, dealers, designers, gemmological laboratories and institutional members across more than 45 countries. Its role is best understood as a combination of trade body, industry voice, ethics watchdog and educational platform.

Foundation and structure

The association was established by leading figures in the post-1980 coloured-stone boom, when a generation of new sources, particularly East African ruby and sapphire, Brazilian and African tourmaline and emerald from Colombia and Zambia, was reshaping the trade. The founders saw that diamond had a unified industry voice through De Beers and the Diamond Trading Company, while coloured stones were fragmented across hundreds of independent businesses with no shared platform. ICA's headquarters has remained in New York. Membership is organised by category, with separate provisions for miners, dealers, cutters and laboratories, and the board is elected from across these categories at the association's congresses.

Congress and the World Coloured Stone Congress

ICA's flagship event is its biennial Congress, held in different gem-producing countries on rotation. Past congresses have been held in Sri Lanka, Brazil, Thailand, Hong Kong, Tanzania, Vietnam and Colombia, among others. The Congress combines technical sessions on origin, treatment and laboratory identification with mine visits, business meetings and the awarding of the ICA Awards, the industry's most senior honours for trade contribution. The InColor magazine, the association's official publication, reports the proceedings and runs technical articles on origin determination, market trends and grading studies.

Trade and policy work

Beyond conferences, ICA acts as the coloured-stone industry's policy voice on issues that cross national borders. It has worked on responsible-sourcing standards, on disclosure rules for treatments such as beryllium diffusion and lead-glass filling, and on the gradual harmonisation of laboratory practices. The association maintains a code of ethics for members and has been an active participant in discussions of the OECD Due Diligence Guidance for Responsible Mineral Supply Chains, in dialogue with the Responsible Jewellery Council and other initiatives in the broader gem and jewellery sphere.

Treatment disclosure leadership

One of ICA's most consequential contributions has been pushing for industry-wide treatment disclosure norms. When beryllium-diffused sapphire emerged in the early 2000s, ICA was central in convening laboratories and dealers to agree on identification protocols and disclosure language. Similar work has been done on lead-glass filled ruby, on cobalt-diffused spinel, and on the various heat and oil treatments common in emerald. Members agree to disclose treatments accurately at every stage of sale, in line with the FTC and equivalent rules elsewhere.

Education and research

ICA supports educational programmes in producing countries, including capacity-building for small-scale miners and cutters, and partners with major laboratories on research projects. The association's collaboration with GIA, AGTA, Gübelin, SSEF and Lotus Gemology, among others, has produced reference databases and origin studies that underpin contemporary laboratory reports.

Relevance to the gem dealer

For a working dealer, ICA membership is one of the standard credentials of trade legitimacy alongside AGTA membership in the United States, the LMHC laboratory committee and individual country bodies. The association's network is the practical backbone of the global coloured-stone trade, and its disclosure norms are the standard by which a member firm operates regardless of where in the world a transaction takes place.