noun
- Plural of nummulite; extinct marine organisms (foraminifera) with coin-shaped shells, abundant in Tertiary deposits and used in geological dating.
Usage: paleontology; geology; technical
Examples
- Nummulites are commonly found in limestone formations from the Eocene epoch.
- Geologists use nummulites as index fossils to date sedimentary rock layers.
- The nummulites in this sample indicate a shallow marine environment.
- Ancient Egyptian pyramids were built with limestone containing nummulites.
- Paleontologists identified the age of the deposit by examining the nummulites present.