title: Correlation of the orientation of stacked aragonite platelets in nacre and their connection via mineral bridges.
abstract: In this work, we studied the correlation of the orientation of stacked aragonite platelets of Haliotis laevigata nacre, using selected area diffraction (SAD) in transmission electron microscopy (TEM). From the position of the center of Laue circle (COLC) within the diffraction patterns the tilt angles of the investigated platelets relatively to a reference platelet (oriented in zone axis) are determined. The strong correlation of the platelets supports the existence of mineral bridges, which connect the stacked platelets and enable a transfer of the platelet orientation during growth. Electron tomography and subsequent reconstruction of the obtained data yield information about the shape of the mineral bridges. The crystalline structure of the material within the mineral bridges was investigated by high resolution TEM (HRTEM).
authors.affiliation: Institut für Biophysik, Universität Bremen, Otto-Hahn-Allee 1, 28359 Bremen, Germany. kgries@ifp.uni-bremen.de
authors.forename: Katharina
authors.initials: K
authors.lastname: Gries
authors.forename: Roland
authors.initials: R
authors.lastname: Kröger
authors.forename: Christian
authors.initials: C
authors.lastname: Kübel
authors.forename: Marco
authors.initials: M
authors.lastname: Schowalter
authors.forename: Monika
authors.initials: M
authors.lastname: Fritz
authors.forename: Andreas
authors.initials: A
authors.lastname: Rosenauer
mesh_terms: D000818:Animals; D002119:Calcium Carbonate / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission / Q000379:methods*; D008974:Mollusca / Q000737:chemistry* / Q000648:ultrastructure
chemical_list: D002119:Calcium Carbonate