Re: How to create green patina on copper rain gutters?

Alan

I had a similar problem on a 160 yr old home ---  one side green, the other 
black. I decided to leave it alone as I didn't want to scurry around on a slate 
tile roof.

You won't hurt anything by trying; you'll start out with bright copper that 
will either go black [copper sulfide] or green [copper carbonate].

True 'verdigris' is copper acetate.It has a bit more of an aqua tint to the 
green.

What will form depends on your location, sun exposure, pollutant exposure, 
prevailing weather conditions, wind, proximity to the ocean etc etc.

If you don't like the black, get rid of it and let Mother Nature do her stuff. 
If it comes back black, don't fight it. 

Don't hold your breath and expect an overnight change -- it's not going to come.

Luck

Ken