It’s not exactly traditional, but lots of ‘alternative’ style jewelry, like my 90’s style captive bead rings, can be found in titanium or niobium, both of which are used in medical/dental implants.
A dedicated piercing/body art shop can probably point you to a number of options. Piercing jewelry has come a long way in the last 30 years. They can now make seamless, removable rings in a variety of materials, and there’s just generally a lot more available than the old industrial-style stuff like mine.
There’s also the possibility of non-reactive plastics, resins, wood (yes, I’ve seen some beautifully carved all wooden earrings).
one absolutely must consider the “SO” appreciation of ‘things jewelry’
I found/bought an amber mucho-billion-years old bug captured/frozen in the amber.
she deems it not significant, and does not wear/carry it.
which, I don’t concur , . . . but that is a cultural issue.
ps: I’ll toss the amber - absolutely keeping the wife…
Visit or contact an independent jeweller and see if the jeweller will swap the stone for one your wife likes. Or consign the amber at a ladies’ consignment shop.
I have 3 pieces of amber. Much more popular in northern Germany, Poland, Scandinavia, and Russia than it is here.