Hello Fargon
If it is antique, or even just an expensive or estate item, you may want to consider an auction house. There is a website for the American Society of Appraisers, which might be a good place to start to try and find an appraiser near you. Don't go with the first appraisal, get a few done, and even then you don't want to sell to the person who does the appraisal.
You could also take it to local jeweler to get an updated written appraisal. Stores in your city with a trustworthy reputation, and have been in business for a long time are best. Also, be sure the jeweler is a certified gemologist.
Take pictures of everything, and sometimes you can get an appraisal online. However, Ebay and craigslist are fraught with deception, and advertising this type of jewelry could get you set up to be robbed or worse.
Its best to let someone else sell it for you (auction house, auctioneer on ebay) they take a percentage, but at least you're safe. You could also consider having it made into something else, or trading with a jeweler for something else. Get your appraisals first so that you know what your working with.
Chase
Chase
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