For purposes of this discussion, a 'decanter' is any alcoholic beverage container other than a standard bottle, and which is further a limited edition. Some are ceramic, some are glass, some are bottles but have some commemorative feature, such as a special label. Other special packaging, such as presentation boxes, are also included. For purposes of this post, they are all decanters.
This is a forum for bourbon enthusiasts, hence the name. Bourbon enthusiasts are not necessarily decanter enthusiasts. Decanter enthusiasts do exist, however. You just won't find very many of them here. There are people who specifically collect Maker's Mark or Jack Daniel's decanters, others who collect Jim Beam decanters. Some people only collect one type, others collect more than one type.
In addition to Maker's, Daniel's and Beam, Michter's produced a lot of decanters, so did McCormick. Eagle Rare and Wild Turkey did a few, as did some other distillers. Kentucky Bourbon Distillers LTD has done a lot of them, mostly for non-U.S. markets.
So, if your discovery is something other than a standard bottle, a 'decanter' as defined above, this probably is not the best place to learn more about it, especially its potential resale value.
Then there is the issue of empties versus fulls. Selling containers that have alcohol in them is a problem because it is illegal in the United States to sell alcohol without a license. There are no exceptions for 'collectibles.' There are no exceptions, period. If the container is empty, no problem. It may be sold like any other possession. Some decanter collectors place a higher value on full containers so their activities tend to be on the down low, but some collectors collect empties and they both tend to congregate at the same places. If you are looking to buy or sell a full decanter, look for people who are trading in the empty ones.
I suggest this post be made a sticky.