14k gold chain with sapphire pendant

Yesterday around 3pm I lost my 14k gold-filled chain necklace near the South Coast Plaza entrance in Costa Mesa, Orange County. It's an 18-inch rope chain with a tiny sapphire-accent teardrop pendant; the back is engraved with my initials, 'JP'. The clasp feels a bit stiff and there's a small kink near it. It is a keepsake from my grandmother and holds sentimental value, and I really need to get it back.