I was surprised exactly how patination is both art and chemistry; controlled oxidation, acids

https://storage.googleapis.com/metal-craftsmanship/serving-home-owners/uncategorized/dormers-you-can-count-on-the-honest-aging-of-hand-fabricated-copper.html

I was surprised just how patination is both art and chemistry; controlled oxidation, acids, and waxes create living finishes that develop with climate yet continue to be protectively secured.