I tried new things on this brooch. The brass stripes on the right side are brazed inlays. I carved out the oxidized steel , fluxed it and brazed brass onto it. The oxide layer prevents to a certain grade that everything around the hollow space is brazed also.
But anyway the piece has to be grinded and sanded down after brazing, until everything is even. Then it has to be oxidized again.
On the left side I plated the sanded steel with copper plating solution. Works very good on steel.

This brooch has to be changed a little bit tomorrow. Some things I realized only when I looked close at the photo.

New version: