Gold-tone necklace with heart pendant

I found a gold-tone necklace this afternoon around 2:45pm in the Mall del Norte parking lot behind the JC Penney on Scott Street in Laredo. It's an 18-inch cable chain with a small heart pendant and a separate tiny star charm tucked near the clasp. There's a faint emerald-green stone in the heart and the back of the pendant is engraved with the initials 'M.J.'. The necklace shows a bit of wear, and the clasp is a standard lobster clasp. If this belongs to someone, I'd really like to help get it back—I'm sure it's sentimental to its owner and I'd be glad to reunite it with them.