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Title: Spherulitic Growth of Coral Skeletons and Synthetic Aragonite: Nature’s Three-Dimensional Printing

Journal Article · · ACS Nano

Coral skeletons were long assumed to have a spherulitic structure, that is, a radial distribution of acicular aragonite (CaCO3) crystals with their c-axes radiating from series of points, termed centers of calcification (CoCs). This assumption was based on morphology alone, not on crystallography. In this paper, we measure the orientation of crystals and nanocrystals and confirm that corals grow their skeletons in bundles of aragonite crystals, with their c-axes and long axes oriented radially and at an angle from the CoCs, thus precisely as expected for feather-like or “plumose” spherulites. Furthermore, we find that in both synthetic and coral aragonite spherulites at the nanoscale adjacent crystals have similar but not identical orientations, thus demonstrating by direct observation that even at nanoscale the mechanism of spherulite formation is non-crystallographic branching (NCB), as predicted by theory. Finally, synthetic aragonite spherulites and coral skeletons have similar angle spreads, and angular distances of adjacent crystals, further confirming that coral skeletons are spherulites. This is important because aragonite grows anisotropically, 10 times faster along the c-axis than along the a-axis direction, and spherulites fill space with crystals growing almost exclusively along the c-axis, thus they can fill space faster than any other aragonite growth geometry, and create isotropic materials from anisotropic crystals. Greater space filling rate and isotropic mechanical behavior are key to the skeleton’s supporting function and therefore to its evolutionary success. Finally, in this sense, spherulitic growth is Nature’s 3D printing.

Research Organization:
Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Basic Energy Sciences (BES); National Science Foundation (NSF); Israel Science Foundation; United States–Israel Binational Science Foundation (BSF)
Grant/Contract Number:
AC02-05CH11231; FG02-07ER15899; DMR-1603192; 312/15; BSF-2010065; BSF-2014035
OSTI ID:
1379910
Journal Information:
ACS Nano, Vol. 11, Issue 7; ISSN 1936-0851
Publisher:
American Chemical Society (ACS)Copyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 43 works
Citation information provided by
Web of Science

References (85)

Solidification of eutectic Ni-Ni3Ti alloys journal September 1976
Nonclassical crystallization in vivo et in vitro (I): Process-structure-property relationships of nanogranular biominerals journal November 2016
Skeletal development inAcropora cervicornis: II. Diel patterns of calcium carbonate accretion journal November 1983
Spherulitic Growth of Calcium Carbonate journal May 2010
Materials become insensitive to flaws at nanoscale: Lessons from nature journal May 2003
Nano to macroscale biomineral architecture of red coral (Corallium rubrum) journal November 2008
Structure of recent and fossil mysid statoliths (Crustacea, Mysidacea) journal January 1993
Microstructural evolution and nanoscale crystallography in scleractinian coral spherulites journal July 2013
Geochemical Perspectives on Coral Mineralization journal January 2003
Skeletal development in Acropora cervicornis: I. Patterns of calcium carbonate accretion in the axial corallite journal June 1982
Structure and growth of platelets in graphite spherulites in cast iron journal January 1994
Sea Urchin Spine Calcite Forms via a Transient Amorphous Calcium Carbonate Phase journal November 2004
Protein Spherulites journal February 1960
Sr/Ca and Mg/Ca vital effects correlated with skeletal architecture in a scleractinian deep-sea coral and the role of Rayleigh fractionation journal September 2007
Nacre tablet thickness records formation temperature in modern and fossil shells journal February 2017
Control and Design Principles in Biological Mineralization journal February 1992
Mollusk Shell Nacre Ultrastructure Correlates with Environmental Temperature and Pressure journal March 2012
Narrowly Distributed Crystal Orientation in Biomineral Vaterite journal September 2015
Biomineral nanoparticles are space-filling journal January 2011
Observations of the tissue-skeleton interface in the scleractinian coral Stylophora pistillata journal June 2007
Immunolocalization of skeletal matrix proteins in tissue and mineral of the coral Stylophora pistillata journal August 2014
Coral Skeletons: An Explanation of Their Growth and Structure journal December 1970
Measurement of c-axis angular orientation in calcite (CaCO3) nanocrystals using X-ray absorption spectroscopy journal June 2011
Impact of seawater acidification on pH at the tissue-skeleton interface and calcification in reef corals journal December 2012
Coral calcifying fluid pH dictates response to ocean acidification journal June 2014
Spherulitic crystallization in biopolymers journal December 1974
Aragonite Crystal Growth and Solid-State Aragonite–Calcite Transformation: A Physico–Geometrical Relationship via Thermal Dehydration of Included Water journal April 2013
Growth and form of spherulites journal July 2005
Influence on the Formation of Aragonite or Vaterite by Otolith Macromolecules journal January 2005
Glass-Crystal Growth Mode for Testosterone Propionate journal October 2011
Spherulitic rhyolites of the Archean Blake River Group, Canada; implications for stratigraphic correlation and volcanogenic massive sulfide exploration journal April 1996
Avian eggshell mineralization: biochemical and functional characterization of matrix proteins journal October 2004
Polarization-dependent Imaging Contrast (PIC) mapping reveals nanocrystal orientation patterns in carbonate biominerals journal October 2012
Oxygen Spectroscopy and Polarization-Dependent Imaging Contrast (PIC)-Mapping of Calcium Carbonate Minerals and Biominerals journal May 2014
Biomimetic type morphologies of calcium carbonate grown in absence of additives journal January 2012
Pseudomorphic transformation of amorphous calcium carbonate films follows spherulitic growth mechanisms and can give rise to crystal lattice tilting journal January 2015
Spherulitic branching in the crystallization of liquid selenium journal April 1991
Late Cretaceous Peruvian eggshells and their relationships with laurasian and eastern Gondwanian material journal January 1997
Spherulitic Crystallization from the Melt. I. Fractionation and Impurity Segregation and Their Influence on Crystalline Morphology journal April 1964
Structure-property relationships of a biological mesocrystal in the adult sea urchin spine journal February 2012
Compensation of charging in X-PEEM: a successful test on mineral inclusions in 4.4Ga old zircon journal December 2003
Mapping amorphous calcium phosphate transformation into crystalline mineral from the cell to the bone in zebrafish fin rays journal March 2010
Mechanism of Calcite Co-Orientation in the Sea Urchin Tooth journal December 2009
Phase transitions in biogenic amorphous calcium carbonate journal April 2012
Quantifying Crystalline Fraction within Polymer Spherulites journal February 2007
Nanoscale Transforming Mineral Phases in Fresh Nacre journal October 2015
In vivo light-microscopic documentation for primary calcification processes in the hermatypic coral Stylophora pistillata journal March 2006
Direct Nanoscale Imaging Reveals the Growth of Calcite Crystals via Amorphous Nanoparticles journal March 2016
Control of Aragonite or Calcite Polymorphism by Mollusk Shell Macromolecules journal January 1996
Particle Accretion Mechanism Underlies Biological Crystal Growth from an Amorphous Precursor Phase journal July 2014
Growth and structure in abalone shell journal January 2005
Formation and ageing of L-glutamic acid spherulites journal April 2010
Architecture of Columnar Nacre, and Implications for Its Formation Mechanism journal June 2007
Crystallographic orientations of structural elements in skeletons of Syringoporicae (tabulate corals, Carboniferous): implications for biomineralization processes in Palaeozoic corals journal September 2014
Crystallization by particle attachment in synthetic, biogenic, and geologic environments journal July 2015
Analogous biomineralization processes between the fossil coral Calceola sandalina (Rugosa, Devonian) and other Recent and fossil cnidarians journal November 2016
The Hierarchical Architecture of Nacre and Its Mimetic Material journal October 2005
Primary biogenic skeletal structures in Multithecopora (Tabulata, Pennsylvanian) journal September 2013
Some studies of deformation processes in fully-spherulitic polypropylene journal February 1971
Mechanism of Calcium Oxalate Monohydrate Kidney Stones Formation: Layered Spherulitic Growth journal February 2010
Polarization-dependent imaging contrast in abalone shells journal February 2008
The two-step mode of growth in the scleractinian coral skeletons from the micrometre to the overall scale journal June 2005
Asprich Peptides Are Occluded in Calcite and Permanently Disorder Biomineral Crystals journal August 2010
Compositional and morphological features of aragonite precipitated experimentally from seawater and biogenically by corals journal July 2009
Spherulites journal November 2011
Supercooled rocks: development and significance of varioles, spherulites, dendrites and spinifex in Archaean volcanic rocks, Abitibi Greenstone belt, Canada journal May 2002
Study of the crystallographic architecture of corals at the nanoscale by scanning transmission X-ray microscopy and transmission electron microscopy journal July 2011
Polymorphic crystalline structure of fish otoliths journal October 1993
Coral Skeleton Construction: A Physiochemically Dominated Process journal April 1986
Crystallization of CaCO 3 in Water–Alcohol Mixtures: Spherulitic Growth, Polymorph Stabilization, and Morphology Change journal December 2011
XANES mapping of organic sulfate in three scleractinian coral skeletons journal January 2003
Isotropic microscale mechanical properties of coral skeletons journal May 2015
CaC2O4H2O spherulites in human kidney stones: morphology, chemical composition, and growth regime [CaC2O4H2O spherulites in human kidney stones: morphology, chemical composition, and growth regime] journal April 2005
Distribution of magnesium in coral skeleton: MG MICRODISTRIBUTION IN CORAL journal December 2004
Stable isotopes in deep-sea corals and a new mechanism for “vital effects” journal March 2003
Biomineralization in newly settled recruits of the scleractinian coral Pocillopora damicornis : Biomineralization in journal June 2014
Self-organisation of nacre in the shells of Pterioida (Bivalvia: Mollusca) journal March 2005
Self-Sharpening Mechanism of the Sea Urchin Tooth journal December 2010
A Phenomenological Theory of Spherulitic Crystallization journal August 1963
Aragonite Precipitation by “Proto-Polyps” in Coral Cell Cultures journal April 2012
An evolutionary fast-track to biocalcification: Fast-tracking biocalcification journal March 2010
Microstructural and physico-chemical characterization of ‘centers of calcification’ in septa of some Recent scleractinian corals journal November 1998
Spherulites and Allied Structures. Part. I. journal January 1941
Spherulitic Crystallization as a Mechanism of Skeletal Growth in the Hexacorals. journal January 1941
Photoemission spectromicroscopy for the biomineralogist book February 2014

Cited By (7)

Protein disorder–order interplay to guide the growth of hierarchical mineralized structures journal June 2018
Structure and Function of Stony Coral Intraskeletal Polysaccharides journal March 2018
Amorphous calcium carbonate particles form coral skeletons journal August 2017
The first tunicate with a calcareous exoskeleton (Upper Triassic, northern Italy) journal March 2018
A rare case of an evolutionary late and ephemeral biomineralization: tunicates with composite calcareous skeletons journal January 2020
Precipitation of silver particles with controlled morphologies from aqueous solutions journal January 2020
Impact of ocean acidification on crystallographic vital effect of the coral skeleton journal July 2019

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