My mom replaced my wedding ring with a cheaper one and said “you’ll never notice”

When I got engaged, my husband (30M) and I picked out a ring together, custom design, meaningful engraving. I love it.

My mom (60F), visiting when I was out, asked to see it. I showed her. She admired it and left with it “for safe keeping.”

A week later, when I found it again, it looked different. I confronted her. She sighed and said, “I swapped it with a cheaper ring temporarily so it doesn’t get stolen abroad. You’ll never notice the difference.”

She still won’t give me back the original one, says she’s keeping it “just in case.”

I feel violated. It’s not money, it’s my symbol.

Should I demand it back and escalate, or try to repair this with her?