I have a never worn classic cathedral solitaire mounting in platinum in a size 5.5 crafted by Victor Canera. It housed an asscher diamond that is 6.96 x 6.91 x 5.02mm. This setting will fit any square or cushion shaped stone within a few mm of the above dimensions and it could possibly fit a round, although if it is a diamond, the diamond would probably be on the higher set side in this setting. This would also be a great setting for a gemstone since the asscher was a tad deep. Thank you! oldcutnut@gmail.com