9CT/375 yellow gold knot earrings -The earrings and fastenings are stamped for 9CT gold Testing confirms 9CT gold (1.34g). 750/18CT yellow gold and smoky quartz earrings -These earrings are stamped '750' for 18CT gold and the butterfly backs are stamped for 9CT gold Testing confirms 18CT (1g) 9CT gold (0.39g).
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