Sterling silver heart necklace, initials EM

I lost my sterling silver heart necklace yesterday around 3pm outside the Covered Market entrance on Cornmarket Street in Oxford. It’s a slim 18-inch chain with a small heart pendant, and the back is engraved with the initials EM. It’s sentimental to me—my sister gave it to me, and I wear it every day—so I’m really hoping it’s found. The chain has a slight tarnish from daily wear and there’s a tiny scratch on the heart that I’d recognize.