Start off with a personal story of how you got the object - It must be awesome. Someone stopped you and pushed it into your hands or someone died and your name was in their will for some odd reason, etc.
Explain how you did research and found the name of the Genie/Djinn and make a huge story of what they were responsible for. Keep reiterating that their story is lost to the dust of time so no matter what your bidders do, they'll never find the information no matter how hard they search.
Take pictures of said objects with a decorative surrounding. Some good examples: lay it on a big crystal cluster, dangle it off the handle of a sword, etc... Warp the images with a paint program. Make it glow, add wisps and smoke. Be creative!
Decorate the ebay lot with lots of flashy backgrounds and images. You want to distract the bidders from reading the endless text because somewhere in there, you have to make the claim that this is purely for 'entertainment purposes' without ruining the overall mysteriousness that you're trying to create over the object.
Don't forget to say that the Djinn/Genie is guaranteed to grant all wishes! Keep saying it every three lines or so.
And that should turn your 99¢ junk into $50 profits.