I am basing it on Shevelev's experience, and as time shows, after a year nothing has changed much. I like the look of the picture, and if the copper will go even more into red shades I will like it even more)) but thanks for the advice!A very interesting experiment, Sergey. Copper is like a chameleon: it’s will change color ever and ever and ……
I think you have to seal it for ‘external influences’ at the moment that the color is how you wanted it.
Regards, Peter