If you’re in the UK, a store like John Lewis or other department store will do them. I think they’re copper because of coppers ‘anti-just about anything’ properties.
Probably only in the UK. Here you can get them anywhere that sells ‘fine’ glassware.
5D2B91EE-0C91-456A-9D41-80A357B13578 by Simon Gibbens posted Nov 14, 2019 at 10:39 PM
Going back to the cleaning discussion, I have had residue right at the bottom of the bottle around the punt that I couldn’t get with a brush. Not sure if you can get these stateside, but in the UK we have something called ‘magic balls’. When you’ve all stopped chuckling, they’re small copper...