Leaves of magnolias and willows are abundant in red sandstone of Cretaceous age that can be found on some beaches on Long Island. In addition, leaves of a relative of the tuliptree, mineralized wood, seeds, and remnants of conifers can be found. Although dinosaurs existed during the Cretaceous Period, no dinosaur fossils have been found on Long Island. This could be due the fact that there are only a few places on Long Island where the Cretaceous sediments are exposed at the surface. In addition to sandstone, the Cretaceous sediments on Long Island include unconsolidated sand and red, white and gray clay.
Mica is intermixed in abundance with much of the Cretaceous sediments.