What are some of the many ways ancient life can be preserved as a fossil? Objective During fossilization, certain characteristics of an ancient organism can become preserved. Students will learn about compression, impression, mold and cast fossils and how they are formed. Students will then create fossil replicas that imitate fossilization processes that are common in the Florissant Fossil Beds area. Background Fossilization is the preservation of ancient life. Any indication, or clue, that an organism lived and interacted with its environment can be an example of a fossil. Unique conditions m Duration: 60 Minutes.