The Open Diamond Pave ring is dsigned to be stackable, meaning you can easily pair it with other rings to create a personalized look that suits your style. Material: Gold Karat: 18K Stone: Diamond Stone Colour: White Number of stones: 12 Stone Carat: 0.12cts Stone Type: VS SI Stone Shape: Round Available sizes: 48,49,50,51,52,53,54,55,56 Can the piece be engraved?: No Does it come with certificate?: No The opening is approx 3-4mm depending on ring size