A group of similar cast gold masks of varying sizes (2.9-8.3 cm. wide) dated to the Warring States period (475-221 BC) are illustrated in Celestial Creations: Art of the Chinese Goldsmith - The Cheng Xun Tang Collection - I- , Art Museum, Institute of Chinese Studies, The Chinese University of Hong Kong, 2007, p. 65, no. A30. The authors note that similar gold plaques have been recovered from tombs of the Spring and Autumn to Warring States periods in Baoji and Fengxiang, Shaanxi province.
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