This charm is made of 92.5 silver. Yin is the black part and is characterized as slow, soft, yielding, diffuse, cold, wet, and passive; and is associated with water, earth, the moon, femininity and nightime.Yang, the white part by contrast, is fast, hard, solid, focused, hot, dry, and aggressive; and is associated with fire, sky, the sun, masculinity and daytime. They measure 10mmx16mm