Biominerals are extraordinary composite materials made by living organisms. Examples of biominerals range from teeth and bones to exoskeletons and shells. The diversity in form corresponds to diversity in function, composition, and structure. Some calcium carbonate (CaCO3) biominerals have highly ordered structures, with nacre (mother-of-pearl) being a prime example where the CaCO3 tablets are intermixed with organic molecules to make a brick wall of incredible strength. Other CaCO3 biominerals have no apparent structure, but rather have CaCO3 crystals oriented in random directions and mixed in no discernable organization with organic molecules. Three of these “disordered” CaCO3 biominerals are the adhesives of the Eastern oyster and a freshwater mussel and the barnacle exoskeleton. To better understand how these materials function, we will explore the structure (light microscopy and scanning electron microscopy with electron backscatter diffraction), composition (energy dispersive x-ray spectroscopy and infrared spectroscopy), and materials properties (hardness and fracture resistance). Students will be involved in all aspects of the project, including putting together all of the pieces to consider functionality for the organism.
One or more of: introductory biology, introductory chemistry, introductory computer science, or introductory physics