The standard of fineness for 18K Gold is 750. This refers to the gold content being 75% gold and 25% being other gold alloys, including palladium and silver. 18K Gold jewellery can appear in white (silvery), black, purple, blue or even rose-colours. It is most commonly seen in white gold because of its strength to withstand normal wear and tear due to its rhodium plating which is extremely hard and it minimizes the jewellery's vulnerability to scratches.