Yaowarat is a world gold trade hub. Thai bullion is soft and yellow from its 97.5 per cent purity. It's sold not in ounces, but in baht (not the currency; one baht weight is 15.2g). Above the elaborate shop of this most famous gold merchant, chain-making workshops and a quaint museum are open by appointment. Other notable gold shops include Hua Seng Heng (332-334 Thanon Yaowarat, 0 2225 0202) and Chin Hua Heng (295-297 Thanon Yaowarat, 0 2224 0077).