Hi all, I am new here so I am not sure whether this is the right place to ask this question or not or whether it would be better in the colored stone bit. I have a vintage ring which currently has a particularly ugly vaguely yellow/brown stone in it. I really like the setting though which has a 8 prong basket for a round stone. I would like to replace the stone , maybe with a spinel or sapphire. I had my jeweller measure the stone which is currently set in it with callipers and it is roughly 6.15mm diameter. My question is what range of diameter stone could i use, : would it have to be exactly the same size or would something between 6 to 6.5 mm do.