THE CROSSED-LAMELLAR STRUCTURE OF MOLLUSK SHELLS AS BIOCOMPOSITE MATERIAL

Composites produced in nature, such as mollusc shells, are renowned for their unique structures and exceptional properties. The crystallographic characterization of different shells as well as their physical and chemical properties have always attracted the interest of researchers. Much information is available at present, however, most of it concerns sea molluscs. We focused on the microstructures and chemical composition of the shell of land snails of the Cepaea genus. New aspects of the microstructure of shells have been shown through the use of a scanning electron microscope (SEM) equipped with an EDS X-ray detector, and X-ray diffractometry (XRD). The study shows that all the tested snail shells are characterized by a typical crossed-lamellar structure and are built of aragonite. Small differences in the chemical composition of the shells as well as differences in the size of the crystallites and different proportions of the amorphous phase were also noticed.