Where is a good place to look for fossils?
A fossil is any evidence of an ancient plant or animal that is preserved in rock. Fossils are common in many of the sedimentary rocks that are found throughout most of Pennsylvania, although in many cases they are only fragments of plant, shell, or bone. Limestone and shale typically are the best rock types for finding fossils, but even sandstones sometimes contain good material. Good places to look for sedimentary rocks are roadsides, streambeds and banks, and quarries or strip mines. Look for places where the roads and streams have cut into hillsides and exposed the rock layers. Fossils of different kinds of animals and plants can be found in rocks of different ages, reflecting the evolution of life forms through time. Fossils are rarely found in Precambrian rocks, which are more than 570 million years old. In the Cambrian, Ordovician, and Silurian Periods (405 to 570 million years ago), fossil seashells that are very different from those found on the beach today can be found in lime
