Cufflinks by Nick Hubbard Features Primary Material : oxidised silver Other Materials : 9ct gold Fitting Type : hinged bar Dimensions (mm) : 13 x 17 x 19 One of a Kind : No Metal : gold 9ct yellow and silver Hallmarked : Yes Cleaning InstructionsIf your jewellery becomes tarnished use a soft, old toothbrush (definitely NO toothpaste!!!) and dip in warm soapy water and brush gently. Rinse in cold water and dry carefully (you could use a hairdryer on a low heat setting). If your jewellery has enamel paint on it, use a cloth impregnated with silver dip to clean your jewellery with.