Things You'll Need
Instructions
Put the medallion on a set of digital scales. You can purchase jewelery scales from online stores specializing in antiques accessories, but a good set of digital kitchen scales ought to serve nearly as well. Make a note of the exact weight down to a few decimal points.
Examine the gold medallion for stamped marks. Usually there will be a karat mark indicating the gold content expressed as a fraction of 24 (so 18 karats or 18K means 18/24ths.) The same information can be presented as parts per thousand. In this case, 18K gold would be indicated by the number 750. See the World Gold Council Website for more information on karatage. If you can't find any marks on your gold medallion, then it's possible to purchase a gold-testing kit online. Alternatively, you can take the medallion into a jewelery store and ask for it to be tested.
Go online and type the words "spot gold price" into your search engine. This will bring up a list of websites showing charts of today's prices for pure gold, usually in dollars and usually changing minute by minute. Take all the information you have gathered, and with a bit of number crunching, you will come up with a fair value for your gold medallion. This will be useful ammunition as you proceed to the next step.
Search the yellow pages under the heading "Gold, Silver and Platinum Buyers and Dealers" for your local dealer in precious metals. At the store, make sure the dealer is willing to buy at the latest spot price and that you both agree on the karat and weight of the coin before clinching a deal. If he offers a fair price, there's no reason why you shouldn't shake hands there and then.
Consider selling online or via traditional auction if you're a bit of a gambler. There is always a chance that two bidders in search of a scarce commodity might pay over the odds. If selling on an online auction site, take pains to accurately state the weight and karatage of the gold medallion. Display photographs of the hallmarks. Place a reserve on it a little below what you would consider to be an acceptable hammer price.