A nummulite is a large lenticular fossil, characterized by its numerous coils, subdivided by septa into chambers. They are the shells of the fossil and present-day marine protozoan Nummulites, a type of foraminiferan. Nummulites commonly reach 6 cm (2.4 inches) in diameter, and are common in Tertiary marine rocks, particularly around the Mediterranean (e.g. Eocene limestones from Egypt). Image above shows the outside and inside of the shell. Foraminifera Nummulites lyelli Middle Eocene (about 37 Ma). Wadi Al-Hitan, El Faiyum, Egypt.
Nummulites laevigatus foraminifera fossil specimens within a beige white limestone matrix, these micro fossils are excellent examples of these amoeboid protists, they exhibit exceptional details, dated to the middle Eocene period .