Fossilized MOSASAUR Jaw Section with 7 Teeth from Morocco. Two of the teeth have cracks and 1 is a partial tooth. The specimen measures 17" Long x 4" Wide x 2.5" Thick and Weighs 3 lbs. Mosasaurs lived during the Late Cretaceous Period, from about 90 million years ago until they went extinct around 66 million years ago. ROCKS FOSSILS MINERALS