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Connoisseur's Choice: Aragonite
Rocks & Minerals, 2015There are many collecting strategies that one may employ to build a collection. Some collectors seek out only rough-and-cut gem minerals, or they may specialize in just one species—calcite is a pop...
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Anisotropic lattice distortions in biogenic aragonite
Nature Materials, 2004Composite biogenic materials produced by organisms have a complicated design on a nanometre scale. An outstanding example of organic-inorganic composites is provided by mollusc seashells, whose superior mechanical properties are due to their multi-level crystalline hierarchy and the presence of a small amount (0.1-5 wt%) of organic molecules.
Boaz, Pokroy +4 more
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Proceedings of the Royal Society of London. Series B. Biological Sciences, 1967
The distribution of aragonite in the skeletal parts of living organisms is reviewed, and its distribution in fossils is described on the basis of several hundred new determinations. Aragonitic fossils are extensively preserved in Tertiary sediments, and are common in Mesozoic rocks, particularly where the enclosing lithology is argillaceous.
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The distribution of aragonite in the skeletal parts of living organisms is reviewed, and its distribution in fossils is described on the basis of several hundred new determinations. Aragonitic fossils are extensively preserved in Tertiary sediments, and are common in Mesozoic rocks, particularly where the enclosing lithology is argillaceous.
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Uranium loss and aragonite–calcite age discordance in a calcitized aragonite stalagmite
Quaternary Geochronology, 2012We analyzed uranium-series concentrations and isotopic ratios in a mixed aragonite and calcite stalagmite from Juxtlahuaca Cave, from the Sierra Madre del Sur of Mexico. The U-series data for the aragonite layers return highly precise and stratigraphically correct ages over the past ca. 4300 years.
Matthew S. Lachniet +3 more
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Comparison of aragonitic molluscan shell proteins
Comparative Biochemistry and Physiology Part B: Biochemistry and Molecular Biology, 2010Acidic macromolecules, as a nucleation factor for mollusc shell formation, are a major focus of research. It remains unclear, however, whether acidic macromolecules are present only in calcified shell organic matrices, and which acidic macromolecules are crucial for the nucleation process by binding to chitin as structural components.
Takeshi, Furuhashi +6 more
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American Journal of Science, 1968
The kinetics of the vaterite-aragonite transformation in aqueous solution were studied to determine the factors involved in aragonite formation. The reaction involved the solution and equilibration of vaterite and subsequent nucleation and growth of aragonite. Extent of reaction was monitored by time-lapse photography.
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The kinetics of the vaterite-aragonite transformation in aqueous solution were studied to determine the factors involved in aragonite formation. The reaction involved the solution and equilibration of vaterite and subsequent nucleation and growth of aragonite. Extent of reaction was monitored by time-lapse photography.
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Nature, 1977
PRESERVATION of aragonite in fossils decreases the further we go back in the geologic record. In the Palaeozoic, aragonitic remains have been found only in clayey–bituminous deposits which have largely inhibited diagenetic alterations of unstable mineral phases (for example, Buck-horn Asphalt and Kendrick Shale, both Upper Carboniferous of USA1, and ...
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PRESERVATION of aragonite in fossils decreases the further we go back in the geologic record. In the Palaeozoic, aragonitic remains have been found only in clayey–bituminous deposits which have largely inhibited diagenetic alterations of unstable mineral phases (for example, Buck-horn Asphalt and Kendrick Shale, both Upper Carboniferous of USA1, and ...
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Aragonite tests among Foraminifera
Journal of Sedimentary Research, 1954Aragonite has been found composing the tests of a few species of Foraminifera, while the tests of an estimated 1,700 to 2,000 species were composed of calcite. The aragonite apparently is quite stable.
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American Journal of Science, 1968
The kinetics of the aragonite-calcite transformation were studied in aqueous solution to determine the factors involved in the process of calcite crystallization and the controlling diagenetic conditions for the aragonite-calcite transformation. The reaction involved the solution and equilibration of aragonite with the solution and the subsequent ...
J. L. Bischoff, W. S. Fyfe
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The kinetics of the aragonite-calcite transformation were studied in aqueous solution to determine the factors involved in the process of calcite crystallization and the controlling diagenetic conditions for the aragonite-calcite transformation. The reaction involved the solution and equilibration of aragonite with the solution and the subsequent ...
J. L. Bischoff, W. S. Fyfe
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Monoclinc aragonite, the precursor of metastable aragonite formation
2019Aragonite is a wide-spread crystalline form of CaCO3 on the Earth surface. Although calcite is the thermodynamically stable CaCO3 form at ambient conditions, aragonite precipitates in the ocean and in some continental settings. It is abundant in the shells of various organisms such as molluscs and corals as well as in stromatolites, and its abiotic ...
Németh P. +5 more
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