How do you get new copper to look naturaly aged green and stable, Verdigris. I have used acids Hydrochloric, Hydroflouric, and find the Verdigris is a top layer and sometimes bluer or darker green than naturaly aged copper.
I have found Toilet bowl cleaner that has Hydrochloric acid is great on old black copper gutters that wont fully turn green, as its already buffered and gelled so it stays wet and doesnt drip on you as you brush it on, and safer to use.
I have fumed copper in a heated tub but the results are darker and more green than natural aging and the finish flakes off. I have heard to sand and or heat the copper with a propane torch and that even Pee is great, this I willl try next. There is a process to make copper green and stable but I dont know it. Revere copper does it. Im on the other side of the pond so excuse my terminology, this week will be back to 0f degree, a bit cold.