Glossary Category: Fossil Formation & Preservation

Formation and preservation terms that explain what was preserved, how it formed, and why specimens vary in detail and stability.

Fully fossilized tree resin that hardened through polymerization over millions of years.
Copal is young, partially fossilized tree resin that looks like amber but is much less mature and can be softer or more prone to damage.
Resin that has hardened and aged over geological time, including amber.
Isotope analysis measures ratios of specific isotopes in a mineral, rock, or fossil material to help interpret origin, age context, or alteration history—useful for supporting provenance or formation claims when the right sample and method are used.
A mosasaur is an extinct marine reptile best known from Late Cretaceous deposits; collectors most often encounter its fossils as teeth, vertebrae, and jaw fragments with distinctive tooth and root features.