Waterproof necklaces- Katie loxton?

[Sandytoesies]

Looking for a waterproof necklace that I can keep on all summer. Has anyone any experience of Katie Loxton waterproof necklaces?
I’ve tried atolea and that stained and ruined a shirt (and my skin). I’ve tried Lovissa and it broke almost immediately.

DD has a gorgeous Swarovski one - the only reason it has been taken off in the past 5 years is for an MRI scan. She showers, bathes, swims in it with no issues. Still looks good as new