Edit: nevermind my craft store has it! Thanks for the help all!

Thank you! So I just want to be sure I understand: the adhesive side is silver so if I were to be soldering together mirrors and clear pieces of glass, it would match the color of the silver solder?

https://www.amazon.com/Studio-4-Inch-Silver-Lined-Copper/dp/B004BNBRUO/ref=mp_s_a_1_5?crid=24HAUQY1U0Z73&keywords=silver+backed+copper+foil&qid=1672790197&sprefix=silver+backed%2Caps%2C289&sr=8-5