Oolitic sand is an unusual sediment found around the Great Salt Lake. The sand, instead of forming grains of minerals, is formed within the Lake and composed of tiny rounded oolites. An oolite has a shell of concentric layers of calcium carbonate around a central core. Oolites form in shallow, wave-agitated water, rolling along the lake bottom and gradually accumulating more and more layers. These grains of sand give the shores of the Great Salt Lake its beautiful and varying colors.