Hello! I'm pretty new to this part of Pricescope but I wanted to share my 8.16 ct oval sphene! I sent it off to Jerry Newman and he partially recut the bottom to give it 18 new pointy facets on the pavilion. I haven't set it yet but here are a few pictures:
Looks good; I've had Jerry cut a similar colored sphene and it turned out great. If yours is like mine you'll get some awesome Dispersion that will shame the best of diamonds. Mine shows off huge rays of red yellow orange and green. If sphene were more durable and well known, I believe it would be worth a lot more.
I would like to share my experience with a sphene ring. I had one set north-south with small sides. (It was smaller than yours and a native cut oval.) It was made into a right hand ring and I am right handed. I didn't wear it very often but after not wearing it for a couple of years I took it out just to try it on. Well, I noticed a sizable chip even though I didn't remember knocking it against anything. I have since had it removed from the setting and recut. Now I admit I am a bit of a klutz but I would never consider setting a sphene in a ring for myself. If you do decide to make yours into a ring. I would recommend having it made for your non-dominant hand.
And to give another example of how easy it is to chip a sphene, I had a different one in a plastic bag on top of a stack (approximately 6 inches high) of paperback books. I knocked it off the stack onto a wooden side table. (Me being klutzy again.) Well, it chipped. It was a small chip, but a definite chip. I had this one repolished and it now resides in a gem box.