Something cropped and structured. Depends on your occasion, of course. You said a wedding? So maybe not denim.
A cropped cardigan would also work if you need something where you'd be likely to find an array of colors, and with jewelry and accessories it'd be more dressy than denim, and more affordable than a full-on tailored jacket (something I think about for special occasions--I don't always want to invest in a whole look unless I can re-mix it with the rest of my wardrobe.