Fossils are familiar to most of us as the hardened, three-dimensional remains of ancient plants and animals, whose tissues have been impregnated by, or replaced with, minerals such as calcite, iron, and silica, thus arresting their inevitable decay. Because the mineralization process results in a rock that’s usually harder than the material around it, especially in the case of petrification, fossils are durable snapshots of the past. But...Continue Reading