title: Microstructure and crystallographic texture of Charonia lampas lampas shell.
abstract: Charonia lampas lampas shell is studied using scanning electron microscopy and X-ray diffraction combined analysis of the preferred orientations and cell parameters. The Charonia shell is composed of three crossed lamellar layers of biogenic aragonite. The outer layer exhibits a 001 fibre texture, the intermediate crossed lamellar layer is radial with a split of its c-axis and single twin pattern of its a-axis, and the inner layer is comarginal with split c-axis and double twinning. A lost of texture strength is quantified from the inner layer outward. Unit-cell refinements evidence the intercrystalline organic influence on the aragonite unit-cell parameters anisotropic distortion and volume changes in the three layers. The simulation of the macroscopic elastic tensors of the mineral part of the three layers, from texture data, reveals an optimisation of the elastic coefficient to compression and shear in all directions of the shell as an overall.
authors.affiliation: Laboratoire CRISMAT-ENSICAEN (CNRS UMR 6508), Université de Caen Basse-Normandie, 6 bd M. Juin, 14050 Caen, France. salim.ouhenia@ensicaen.fr
authors.forename: S
authors.initials: S
authors.lastname: Ouhenia
authors.forename: D
authors.initials: D
authors.lastname: Chateigner
authors.forename: M A
authors.initials: MA
authors.lastname: Belkhir
authors.forename: E
authors.initials: E
authors.lastname: Guilmeau
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D002119:Calcium Carbonate; D005109:Extracellular Matrix; D008855:Microscopy, Electron, Scanning; D012908:Snails / Q000033:anatomy & histology* / Q000648:ultrastructure*; D014961:X-Ray Diffraction
chemical_list: D002119:Calcium Carbonate