This piece is on a large piece of driftwood, there is a layer of blue acrylic paint to give a 'blue' feeling. The stones are smooth gray beach stones from Lake Michigan. The stones reminded me of minnows, as they bump your knees underwater in the shallow areas.
In between the gray stones are crinoids, marine animal fossils, or if you picked them up as a kid maybe you called them Indian beads. Some are textured with a star in the center others are rougher and more broken. Check out the close up pics to see the crinoids at https://www.etsy.com/shop/beachwalkartbykim