My photographic patina

The effect is metals exposed to acid designed to corrode the copper shavings inside the paint. It looks very similar to the effect I have been able to create in one of my images, the image itself didn't have that much interest to me when I created it, but since further exploring the idea the context of my image is still there, I need to find a way to control the corrosive qualities of the pesticide so I can have more of my content showing.

An example of a copper patina. ( unknown artist)