Board Thread:Oblivion/@comment-67.142.168.143-20130719075642/@comment-6881629-20130719092945

I think with Oblivion you click on the gem to get the option (Skyrim you click the weapon) i think...

The easier option is if you have plenty of Septims go to a Mages Guild one npc in every Guild will rechage items for money (one of the little icons under the dialog options). It can be a bit expensive early on in the game though.