Rings by Josef Koppmann The ring is forged of sterling silver, 24ct gold has been fused on to the silver and the rutilated quartz is set in 24 carat gold. Features Primary Material : 24ct gold, rutilated quartz and sterling silver One of a Kind : Yes Metal : 24ct yellow gold and sterling silver Hallmarked : Yes Cleaning InstructionsThe ring is best kept clean by rubbing and brushing it gently under running water with bicarbonate of soda.