If he said it's out of his league to appraise then I'm guessing it's over 10K and probably in the 20+K league perhaps. A ring like that will not only pay for your machine, but several other machines to sit along side your GT for when the mood strikes you to go for some "strange", and also for several nice coils, with still a good chunk of cash left over to smooze the lady in your life so she'll let you go out and hunt for more stuff.
I've got a friend who is a gold smith, who repairs, makes, and re-sizes rings for jewelers and also individual customers, so here's the scoop on that- Jewelry store owners can get a diamond on loan from their supply with no cash up front, to shop around to customers, and then if they make a sell they pay the wholesale price for it to the supplier. So, people get upset when a jewelry store owner doesn't offer them nearly the same amount of what a similar ring might sell for in their stores. People have to understand that in order for him to be motivated to buy a stone off somebody, the price must be a good bit lower than what they can get a similar stone for "free" on loan from their supplier. They are tying their money up with paying for a stone, so to make it worth their effort they need a bigger profit potential on it than one they sell from a supplier.
Years ago I found a nice ring. I had it shopped around out of curiosity by him. The price I was offered through my gold smith friend who shopped it around to jewelers was either $2900 or $3900, I forget which. Anyway, was told retail on a similar stone in weight/quality was about 10K. It was a very high quality stone with very good clearity. 2 carrot or 3 carrot, I forget which off hand it's been so many years ago.
So, if you look at that ring as "found" money, then take what you can get for it, but if you want to squeeze every last dime out of it get it appraised and then sell it a bit below retail value yourself to the general public. Be VERY careful though, from the looks of it that's the kind of ring that can get somebody hurt. If you do Ebay or such, be darn sure you know who you are dealing with in terms of scams. Personaly I'd do a local Craig's List ad and only meet the person in public view in say a coffee shop. Cash on the barrel head. No checks or money orders, which can all be faked. If you price it say 2K or so below what a person could get it for retail that might be enough to motivate a buyer.
Also, sometimes it's more easy to get an asking price by having the diamond removed and selling that alone. People are picky about rings. They might just want the stone. Going that route, not only will you get a good hunk of change for the stone, but you also get to scrap the gold too.
You are one lucky man. For sure that ring qualifies for a find of a life time. All down hill from here though...Just kidding...
