Hong Kong native Tania Chan has designed high jewellery (haute joaillerie) for the past 17 years. The mother of two wears many hats; she’s a lecturer at L’ecole, School of Jewellery Arts (supported by jewellery house Van Cleef & Arpel’s), teaching Gouache. As a GIA-certified gemologist, metallurgist, and jewellery designer, she also leads the creative direction of Osmium, the rarest precious metal in the world, and works at her high-end jewellery atelier, Alchemist.
Chan is fluent in French, English, Cantonese, and Mandarin and easily switches between the languages with her poetic descriptions of gouache, a traditional technique from the 18th century using paint pigments to capture precise three-dimensional designs on a 1:1 scale that jewellers use to craft pieces.
Chan stresses the importance of accuracy and precision. “Even the tiniest details of the prong, we must paint it exactly as it is. Gouache is the blueprint for the team to look at for reference,” she said. “For the gemologist to pick up the gemstone with the same saturation of the gem’s colours, we must paint it with absolute precision. If the ruby is pigeon blood red or a vivid red, you’d better paint it right. Without speaking, based on the gouache, the jewellery team will know precisely how to make it come alive.”
At the annual trade show GemGeneve in Switzerland in May 2025, Chan conducted a series of Awakening the Senses workshops on Osmium gouache. There, she introduced an innovative modern technique to the centuries-old craft. Chan spent six months studying and experimenting with different brushes and brush stroke techniques before finally finding one that worked, creating a traditional three-dimensional gouache that comes alive with the texture of Osmium.
