My girlfriend is Jewish and I've been wanting to propose for a while now, but with no money coming in from my job I can't afford to get her a proper ring.

Would it be suitable to get a circumcision (showing how much I respect her religion) and use the foreskin as an engagement ring? I'm not too sure how it would would work and can't think of anything to replace the diamond with so if anyone has any suggestions It would be much appreciated.

Thank you