Searching for Sand Rubies

After the Tucson summer rains would fill the arroyos and washes around our house when I was young  and the water would disappear as quickly as it came, I would walk along the damp, smooth sand searching for sand rubies. I would collect the small, dark red stones in a white handkerchief and bring them home to show my mother. I would unfold the cloth and lay it flat on the kitchen table. The rubies would glisten and dance against the white material like so many red birds.