Gold-tone heart pendant necklace with ruby

I lost my gold-tone heart pendant necklace yesterday around 3pm on Newbury Street near the Boston Public Garden's Arlington Street entrance. It's a slender 16-inch chain with a small ruby set in the center of a heart pendant, and the back is engraved with 'MZ.' There's a tiny wear mark near the clasp. This necklace was a gift from my grandmother and has a lot of sentimental value; I really need it back. If you’ve seen it or picked it up, please reach out—I'll be forever grateful to get it back.