http://devestechnet.com/Images/Projects//HeaterRestore/heater18lg.jpgfrom here:
http://devestechnet.com/Home/HeaterRestoreThat is about the best picture I have of what Hammerite Rust Cap Bronze used to duplicate what the original heater looked like. You can see what they are talking about, however, I think it came out really nice. But Denny is right, there is no way to really duplicate those old hammered finishes better.