Post Firing- BC Hollow Forms

Just a quick shot of the fired bronzclay hollow forms- my free form number hollow bead on the right developed a few fine cracks and must have had a weak spot of the back since it has the most damage. It was fired on its side, so maybe I sanded it too much- can't say as I really remember since the forms were made more than a year ago.
I'd like to get a nice patina on them that is a little more permanent than what the firing medium gives. Any suggestions?