Silver necklace with sapphire pendant, lost in Charleston

I lost my delicate 18-inch sterling silver necklace with a small sapphire pendant yesterday around 3pm. The chain is thin and polished, with a tiny lobster clasp, and the pendant is a 6mm teardrop sapphire set in a simple bezel. The back of the pendant has a faint initial 'P' engraved and there are a couple micro-scratches along the chain from daily wear. I think I last had it when I stepped out of the Charleston City Market on Meeting Street, near the Market's south entrance. It means a lot to me—it was a gift from my grandmother, and I really need it back.