Gold chain necklace with heart pendant

I lost my gold chain necklace yesterday around 3pm near Campustown Coffee Shop on Welch Ave in Ames. It's a delicate 18-inch gold chain with a tiny heart pendant engraved with 'M+' on the back, and there's a small scratch on the surface. The necklace is sentimental to me because it was a gift from my grandmother and I wear it every day. If anyone spotted it or picked it up, I’d really appreciate it — I can meet you near the coffee shop or at the ISU campus shuttle stop to get it back.