re: Another few days in the shop

Thanks for the link OT 👍
I really like checking out these peoples work.
I did get something that'll work.

Craftisian's own Brian Benham does exceptional work:

Basically acid (vinegar) = greens
ammonia = blues
sodium (salts + heat) = red

I find that having something to absorb whatever (like a sponge) in contact with the copper can really add "texture" versus just a solid color.
I did this with my clock face from some time back

Coarse salt has the same effect, pulling out localized color, usually light blue with ammonia.