Biomineral reactivity: the kinetics of the replacement reaction of biological aragonite to apatite ...

• Main Authors: Greiner, Martina, Férnandez-Díaz, Lurdes, Griesshaber, Erika, Zenkert, Moritz N., Yin, Xiaofei, Ziegler, Andreas, Veintemillas-Verdaguer, Sabino, Schmahl, Wolfgang W.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Universität Ulm 2018
• Subjects: Bioaragonite; Dissolution-reprecipitation; Mineral replacement; DDC 540 / Chemistry & allied sciences; DDC 620 / Engineering & allied operations; Apatite; Microstructure; Apatit; Mikrostruktur; Arctica islandica
• Online Access: https://dx.doi.org/10.18725/oparu-39985; https://oparu.uni-ulm.de/xmlui/handle/123456789/40061

We present results of bioaragonite to apatite conversion in bivalve, coral and cuttlebone skeletons, biological hard materials distinguished by specific microstructures, skeletal densities, original porosities and biopolymer contents. The most profound conversion occurs in the cuttlebone of the cephalopod Sepia officinalis, the least effect is observed for the nacreous shell portion of the bivalve Hyriopsis cumingii. The shell of the bivalve Arctica islandica consists of cross-lamellar aragonite, is dense at its innermost and porous at the seaward pointing shell layers. Increased porosity facilitates infiltration of the reaction fluid and renders large surface areas for the dissolution of aragonite and conversion to apatite. Skeletal microstructures of the coral Porites sp. and prismatic H. cumingii allow considerable conversion to apatite. Even though the surface area in Porites sp. is significantly larger in comparison to that of prismatic H. cumingii, the coral skeleton consists of clusters of dense, ...