It contains many fossils, especially those of the foraminifera "Globigerina" that give it its name. The building is a masterpiece in sculpture in Maltese globigerina limestone. For example, there are diatom, coccolith, foraminifera, globigerina, pteropod, and radiolarian oozes. The base of the sea is made up of globigerina ooze. The softer globigerina was used for decorative elements within the temples, usually carvings. Its builders used the soft globigerina limestone that caps the ridge to construct the temple.