Thanks for the responses everyone, AGGIGS funny you should mention a larger size because my mother chipped it when she tried to wear the ring my father had it originally set in. I have no idea the weight but it was a large concoidal off one corner the caused the repair cut. That is why it was re-set in a safer pendent (not to mention an 80+ct stone in a ring was cartoonish even in the 70’s).
Tourmaline thank you for the input! Do you perhaps know if any of the “major” labs will do a partial report prior to cutting for ID purposes and finish it after the cutter returns it to them after the cut?