Sterling silver sapphire ring, sentimental heirloom

I lost my sterling silver ring with a tiny blue sapphire yesterday around 3pm near the Arc of Dreams in downtown Sioux Falls, along the sidewalk by Main Avenue. It's a slim 3mm band with a bezel-set sapphire, with a little tarnish along the edges and a tiny nick on the inner edge that’s easy to spot up close. Inside the band there’s an engraving that reads 'A+M 2012' and a faint scratch near the setting. It means a lot to me—it's a family heirloom from my grandmother, and I’d really love to have it back.