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Updated: May 18, 2026
09:31
Calcium Carbonate Formation in the Presence of Biopolymeric Additives
Published on: May 14, 2019
Biogenic calcite granules--are brachiopods different?
Alberto Pérez-Huerta1, Yannicke Dauphin, Maggie Cusack
1Department of Geological Sciences, The University of Alabama, Tuscaloosa, AL 35487, USA. aphuerta@as.ua.edu
Micron (Oxford, England : 1993)
|October 3, 2012
Summary
Brachiopod shell biomineralization is complex and unique. New research reveals distinct nanostructures and protein envelopes in calcite fibers, highlighting diverse mechanisms in carbonate-producing organisms.
Area of Science:
- Biomineralization
- Paleontology
- Materials Science
Background:
- Brachiopods remain understudied regarding biomineralization.
- Calcitic shells in some brachiopod taxa exhibit complex biomineral structures.
Purpose of the Study:
- To analyze the nanostructure of calcite biominerals in brachiopod shells.
- To investigate the mechanisms of carbonate biomineralization within the phylum Brachiopoda.
Main Methods:
- High-resolution scanning electron microscopy (SEM).
- Atomic force microscopy (AFM).
Main Results:
- Identified distinct nanostructures in semi-nacre tablets and calcite fibers.
- Semi-nacre tablets comprise spherical aggregates of sub-rounded granules.
- Fibers consist of large, triangular or rod-like particles made of small sub-rounded granules (40-60 nm).
Conclusions:
- Carbonate biomineralization mechanisms vary within brachiopods.
- Proteinaceous envelopes around calcite fibers have a dual role: granule production and organic templating.
- Brachiopod shells display a unique biomineralization style among carbonate-secreting organisms.
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