Articles | Volume 18, issue 3
https://doi.org/10.5194/bg-18-775-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-18-775-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Technical note: A universal method for measuring the thickness of microscopic calcite crystals, based on bidirectional circular polarization
Aix Marseille Univ, CNRS, IRD, INRAE, Coll. France, CEREGE,
Aix-en-Provence, France
Yves Gally
Aix Marseille Univ, CNRS, IRD, INRAE, Coll. France, CEREGE,
Aix-en-Provence, France
Baptiste Suchéras-Marx
Aix Marseille Univ, CNRS, IRD, INRAE, Coll. France, CEREGE,
Aix-en-Provence, France
Patrick Ferrand
Aix Marseille Univ, CNRS, Centrale Marseille, Institut Fresnel,
Marseille, France
Julien Duboisset
Aix Marseille Univ, CNRS, Centrale Marseille, Institut Fresnel,
Marseille, France
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Short summary
The coccoliths are major contributors to the particulate inorganic carbon in the ocean. They are extremely difficult to weigh because they are too small to be manipulated. We propose a universal method to measure thickness and weight of fine calcite using polarizing microscopy that does not require fine-tuning of the light or a calibration process. This method named "bidirectional circular polarization" uses two images taken with two directions of a circular polarizer.
The coccoliths are major contributors to the particulate inorganic carbon in the ocean. They are...
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