By far the most familiar gong to most Westerners is the chau gong or bullseye gong. Large chau gongs, called tam-tams have become part of the symphony orchestra. Sometimes a chau gong is referred to as a Chinese gong, but in fact, it is only one of many types of suspended gongs that are associated with China.
A chau gong is made of copper-based alloy, bronze, or brass. It is almost flat except for the rim, which is turned up to make a shallow cylinder. On a 10-inch (25 cm) gong, for example, the rim extends about 1⁄2 inch (1 cm) perpendicular to the surface. The main surface is slightly concave when viewed from the direction to which the rim is turned. The centre spot and rim of a chau gong are left coated on both sides with the black copper oxide that forms during manufacture; the rest is polished to remove this coating. Chau gongs range in size from 7 to 80 inches (18 to 203 cm) in diameter.