Cleaning brass or copper

Isn’t this lovely? But I suspect this was only brass plated or painted. Since you have cleaned the piece lovingly, I suggest you spray paint it brass or copper, then finish it with highlights of burnished copper, and even seal it with polyethylene. Or painting it a bright blue, with burnishing wax, keeps coming to my mind. Enjoy your treasure. ☺️

I've always used Brasso for brass. I don't know if it is more effective than what you've already used.

You have run through a bunch of products already!

Next I would try plain white toothpaste, if that did not work then use Brasso, sold at stores like Walmart, K Mart, some grocery stores, & DIY's.

I would try baking soda and water into a paster and apply with a soft cloth

Use lemon juice with salt and a very fine sand paper

All of these ideas are the go to first, but if you have no success Brasso it is as your final shot. If it was plated as suggested then sanding and painting the colour you wish is the only way to go because redipping to plate it again is astronomical!! Well done with all the suggestions everyone.

There is a product for cleaning copper. Try that.

I have used warm vinegar and baking soda. After is clean, paint clear varnish.

use “never Dull” I use it twice a year just before Easter and just before Christmas on all my silver, brass, copper works well but be sure to not leave any on the item I was in warm soapy water after and dry with soft absorbent cloth. No heavy rubbing necessary works great on aluminium and stainless steel on boats too.

Here's a tutorial that might help - https://chascrazycreations.com/copper-cleaning-hacks/