A set of percussion instruments dating back to the Eastern Zhou Dynasty (770-256 BC) comprises ten pieces crafted from grayish-blue shale with a fine texture. Known as stone bianqing (chime stones), they produce a clear and crisp tone. Each of them is 40 centimeters long, 17 cm high, and 2.5 cm thick. Collection: Houma Jin State Ancient Capital Museum in Linfen city, Shanxi province.