Looking to purchase a vintage ring from an online retailer (am I allowed to name the shop!?) which has stated all their jewelry comes with a GAI (http://gailab.org/ )appraisal. I looked into this "3rd party appraisal company" located in the diamond district and was unable to find a ton of information besides the fact this company states all their appraisers are GIA graduates. The ring in question has .70 total carats (a few larger diamonds and then smaller ones) of F color and VS quality for a little more than $2000. The seller has been accommodating with all my questions, has sent additional pictures, and has a return policy. The sellers also state they are GIA graduates and respected in the jewelry buying/estate jewel business. I guess my question is...is this a legit company GAI? If it isn't, how much lower in quality or discrepancy could there be? I could provide the shop name (seller of the ring), but unsure if that violates community guidelines...Looking to see if I should take the plunge and purchase or keep on walking.