BronzClay Pieces

I've been working with BronzClay for several months now, loving it and trying to get a consistent patina in the process. I think that may be a losing battle, as I can't find any links between fantastically colorful batches and brown batches with no patina at all. I have had to resolve to 'take what I get' and am thrilled when I open the kiln to color!!! The 2 pictures above are from pretty colorful firings!