The Textural Motif of Foliated Calcite in Ostreoidea (Mollusca)
Metadatos
Mostrar el registro completo del ítemAutor
Griesshaber, Erika; Sancho Vaquer, Anna; Checa González, Antonio G.; Salas, Carmen; Harper, Elizabeth M.; Schmahl, Wolfgang W.Editorial
MDPI
Materia
Turbostratic texture High-resolution EBSD Assembly of folia and foliated units
Fecha
2025-03-04Referencia bibliográfica
Griesshaber, E.; Sancho Vaquer, A.; Checa, A.G.; Salas, C.; Harper, E.M.; Schmahl,W.W. The Textural Motif of Foliated Calcite in Ostreoidea (Mollusca). Crystals 2025, 15, 244. [https://doi.org/10.3390/cryst15030244]
Patrocinador
German Research Council Programmes GR 9/1234, SCHM930/11-2; Projects PID2023-146394NB-I00 and PID2020116660GBI00 (SpanishMinistry of Science and Innovation: MCIN/AEI/10.13039/501100011033/)Resumen
The microstructure of bivalve foliated calcite is extraordinary. It consists of
units formed of stacks of folia with individual folia consisting of arrowhead-ended crystal
laths. We investigated the texture of the foliated microstructure, the texture of individual
and arrays of folia and the texture of assemblies of foliated units of the gryphaeid oyster
Hyotissa hyotis with low kV, high-resolution, electron backscatter diffraction (EBSD). We
base our understanding of the foliated texture on the combined interpretation of crystallographic
aspects of individual and stacks of folia with the nature of crystal organization in a
folium, a foliated unit and in foliated unit aggregations. Calcite c- and a*-axes arrangement
in a folium is single-crystal-like. Due to the parallel organization of adjacent laths in a
folium and the stacked arrangement of folia in a foliated unit, the assembly of calcite c- and
a*-axes in foliated units is graded. The result is a ring-like distribution of c- and a*-axes
orientations in the pole figures; nonetheless, the orientation rings are substructured by cand
a*-axes orientation clusters. The direction of the arrowhead endings of the laths is
coincident with the growth direction of the shell. The morphology of arrowheaded laths
initiates the formation of planes with {105}, {106} directions and a parallel orientation to
the inner shell surface. H. hyotis’s foliated microstructure has a specific texture that is
not fully understood. We discuss axial, spherulitic, turbostratic-like textures the foliated
microstructure and suggest that the foliated texture of H. hyotis can, to some degree, be
described with a turbostratic pattern.