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nacre

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Journal Article

Remarkable preservation of shell microstructures from the Late Ordovician of the Cincinnati Arch region, USA, and the success of nacre among Ordovician mollusks

Michael J. Vendrasco, Antonio G. Checa, William P. Heimbrock
Published: 01 July 2019
Journal of Paleontology (2019) 93 (4): 658–672.
DOI: https://doi.org/10.1017/jpa.2018.106
... the most detailed record of Ordovician mollusk shell microstructures, as well as exceptional details on the earliest cases of undisputed nacre. The trend towards nacre in the Mollusca is one aspect of the surge in escalation between mollusks and their predators during the Great Ordovician...
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View PDF for article title, Remarkable preservation of shell microstructures from the Late Ordovician of the Cincinnati Arch region, USA, and the success of <span class="search-highlight">nacre</span> among Ordovician mollusks
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Journal Article

UNALTERED NACRE FROM THE PENNSYLVANIAN BUCKHORN ASPHALT, AND IMPLICATIONS FOR THE ARMS RACE BETWEEN MOLLUSKS AND THEIR PREDATORS

MICHAEL J. VENDRASCO, ANTONIO G. CHECA, RICHARD L. SQUIRES, CARLOS M. PINA
Journal: PALAIOS
Published: 09 October 2018
PALAIOS (2018) 33 (10): 451–463.
DOI: https://doi.org/10.2110/palo.2018.007
... (EBSD), and Atomic Force Microscopy (AFM) reveal a striking high fidelity of preservation, including the oldest known unaltered nacre tablets in gastropods, bivalves, and cephalopods. These nacre tablets are indistinguishable from modern representatives in nanoscale morphology and crystallographic...
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View PDF for article title, UNALTERED <span class="search-highlight">NACRE</span> FROM THE PENNSYLVANIAN BUCKHORN ASPHALT, AND IMPLICATIONS FOR THE ARMS RACE BETWEEN MOLLUSKS AND THEIR PREDATORS
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Journal Article

Calcium carbonate bio-precipitation in counter-diffusion systems using the soluble organic matrix from nacre and sea-urchin spine

Maria Sancho-Tomás, Simona Fermani, Jaime Gómez-Morales, Giuseppe Falini, Juan Manuel García-Ruiz
Published: 01 August 2014
European Journal of Mineralogy (2014) 26 (4): 523–535.
DOI: https://doi.org/10.1127/0935-1221/2014/0026-2389
...Maria Sancho-Tomás; Simona Fermani; Jaime Gómez-Morales; Giuseppe Falini; Juan Manuel García-Ruiz Abstract The biomineralization process of nacre and sea-urchin spine occurs under the biological control of specific macromolecules in gelling environments through diverse mechanisms. In both cases...
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Includes: Supplemental Content
Journal Article

The origin of the color of pearls in iridescence from nano-composite structures of the nacre

Michael R. Snow, Allan Pring, Peter Self, Dusan Losic, Joe Shapter
Published: 01 October 2004
American Mineralogist (2004) 89 (10): 1353–1358.
DOI: https://doi.org/10.2138/am-2004-1001
...Michael R. Snow; Allan Pring; Peter Self; Dusan Losic; Joe Shapter Abstract The origin of the variety of body colors exhibited by South Sea Pearls is in part due to a newly recognized structure of the nacre, the edge-band structure, which gives rise to interference colors characteristic of its...
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Journal Article

NACRE IN LATE CRETACEOUS SENSUITROCHUS FERRERI —IMPLICATIONS FOR THE TAXONOMIC AFFINITIES OF THE CIRRIDAE (GASTROPODA)

STEFFEN KIEL, JIRÍ FRÝDA
Published: 01 July 2004
Journal of Paleontology (2004) 78 (4): 795–797.
DOI: https://doi.org/10.1666/0022-3360(2004)078<0795:NILCSF>2.0.CO;2
... of a nacreous inner layer in a Mesozoic cirrid. This observation was from an unpublished master's thesis ( Hänsel, 1992 ) supervised by him. Hänsel (1992) demonstrated that nacre is present in shells of the Late Cretaceous cirrid Sensuitrochus ferreri Quintero and Revilla, 1966 ( Fig. 1.1 ), using peels...
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Journal Article

Nacre in an early gryphaeid bivalve (Mollusca)

Christopher A. McRoberts, Joseph G. Carter
Published: 01 November 1994
Journal of Paleontology (1994) 68 (6): 1405–1408.
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Journal Article

Caswellsilverite, NaCrS 2 : a new mineral in the Norton County enstatite achondrite

Akihiko Okada, Klaus Keil
Published: 01 February 1982
American Mineralogist (1982) 67 (1-2): 132–136.
...Akihiko Okada; Klaus Keil Abstract Caswellsilverite, NaCrS 2 , occurs in the Norton County enstatite achondrite as anhedral grains up to 1 mm in size. It is associated with daubréelite, titanoan troilite, ferromagnesian alabandite, oldhamite, kamacite, perryite, and a dark-gray phase, also a new Na...
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Book Chapter

Jadeite NaAl[Si 2 O 6 ]: Kosmochlor NaCr[Si 2 O 6 ]

Author(s)
W. A. Deer, FRS, R. A. Howie, J. Zussman
Book: An Introduction to the Rock-Forming Minerals
Publisher: Mineralogical Society of Great Britain and Ireland
Published: 01 January 2013
EISBN: 9780903056434
View PDF for content titled, Jadeite NaAl[Si 2 O 6 ]: Kosmochlor <span class="search-highlight">NaCr</span>[Si 2 O 6 ]
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Image
Shell microstructure in modern mollusks, for comparison with fossil imprints. All images electronically inverted to allow direct comparison with the internal molds. (1) Aragonitic nacre-like tablets in the vetigastropod Ethminolia Iredale, 1924, LACMIP 14806; (2) foliated aragonite in the monoplacophoran Micropilina, LACMIP 14807; (3) nacre tablets in the bivalve Pteria hirundo, LACMIP 14808; (4) incipient nacre tablets in the bivalve Nucula, LACMIP 14809; (5) nacre tablets in the bivalve Pinctada martensii (Dunker, 1880), LACMIP 14810; (6, 7) nacre growth towers (6) and nacre tablets in the septum (7) of Nautilus pompilius Linnaeus, 1758, LACMIP 14811; (8) foliated calcite in the bivalve Anomia ephippium Linnaeus, 1758, LACMIP 14812. Scale bars are (1, 7) 10 μm; (2–6, 8) 3 μm.

Shell microstructure in modern mollusks, for comparison with fossil imprint...

Published: 01 July 2019
Figure 2. Shell microstructure in modern mollusks, for comparison with fossil imprints. All images electronically inverted to allow direct comparison with the internal molds. ( 1 ) Aragonitic nacre-like tablets in the vetigastropod Ethminolia Iredale, 1924 , LACMIP 14806; ( 2 ) foliated
Image
Morphological diversity of calcium carbonate biomineral microstructures in metazoans. A: outer shell layer of the bivalve Venerupis philippinarum. The microstructure is composite prismatic (aragonite). B: nacre and prism layers of the shell of a juvenile fan mussel Pinna nobilis: the prismatic layer (top) is calcitic, while the subjacent nacre layer is aragonitic. C: larval skeleton (high-Mg calcite) of the sea urchin Arbacia lixula. D: tip of a high-Mg calcite spine of the sea urchin Arbacia lixula. E: nacre layer of the shell of the African unionid freshwater bivalve Pleiodon speckii. Note the typical brick-wall microstructure of this type of nacre, commonly found in pteriomorphid and paleoheterodont bivalves. F: spicules of the ascidian Herdmania momus. These biominerals, made of the thermodynamically-unstable vaterite polymorph, exhibit a surprising complexity of their architecture.

Morphological diversity of calcium carbonate biomineral microstructures in ...

Published: 01 April 2014
Fig. 1 Morphological diversity of calcium carbonate biomineral microstructures in metazoans. A: outer shell layer of the bivalve Venerupis philippinarum. The microstructure is composite prismatic (aragonite). B: nacre and prism layers of the shell of a juvenile fan mussel Pinna nobilis
Image
The fracture-characteristic log (ACR) based on the acoustic log (AC) of well N1. In the electrical image log (X-tended Range Micro Imager [XRMI]), the lines indicate fractures; the arrows show fractures with dip-angles of nearly 90° that could not present sinusoids in the image log; the rectangle displays the fractured zones near a fault. See Figure 1 for the location of well N1. CACR = calculated difference ratio of AC; NACR* = normalized CACR; NACR = NACR* for fractures; Vsh = shale content.

The fracture-characteristic log (ACR) based on the acoustic log (AC) of wel...

Published: 01 September 2016
; the rectangle displays the fractured zones near a fault. See Figure 1 for the location of well N1. CACR = calculated difference ratio of AC; NACR* = normalized CACR; NACR = NACR* for fractures; V sh = shale content.
Image
Schematic illustrations of the arrangement of aragonite tiles in columnar nacre (above) and in sheet nacre (below). After Wang et al. (2001).

Schematic illustrations of the arrangement of aragonite tiles in columnar n...

Published: 01 November 2005
F igure 1. Schematic illustrations of the arrangement of aragonite tiles in columnar nacre (above) and in sheet nacre (below). After Wang et al. (2001) .
Image
(1–5) Shell microstructure (nacre) imprints on internal molds of the hinge region of the bivalve Lyrodesma sp. from the Ordovician Fairview Formation of Kentucky (LACMIP Locality 41961). (1, 2) LACMIP 14816; (3) LACMIP 14817; (4) LACMIP 14818; (5) LACMIP 14819. (6–9) Shell microstructure (nacre and nacre-like) imprints on steinkerns of the bellerophontiform Cyrtolites sp. from the Ordovician Fairview (6, 7) and Point Pleasant (8, 9) formations. Numbers show measurements of well-preserved interfacial angles. (6, 7) LACMIP 14820 (LACMIP Locality 41961); (8, 9) LACMIP 14821 (LACMIP Locality 41960). Scale bars are (1, 6) 10 μm; (2, 7) 5 μm; (3) 2 μm; (4, 5) 3 μm; (8, 9) 1 μm.

( 1 – 5 ) Shell microstructure (nacre) imprints on internal molds of the hi...

Published: 01 July 2019
Figure 5. ( 1 – 5 ) Shell microstructure (nacre) imprints on internal molds of the hinge region of the bivalve Lyrodesma sp. from the Ordovician Fairview Formation of Kentucky (LACMIP Locality 41961). ( 1, 2 ) LACMIP 14816; ( 3 ) LACMIP 14817; ( 4 ) LACMIP 14818; ( 5 ) LACMIP 14819. ( 6–9
Image
SEM views of the analysed thin sections. (a) Psilunio littoralis shell section showing the transition between the external aragonitic prismatic layer and the nacreous inner layer. (b) View of the entire thickness of the Nautilus belauensis sample showing the different microstructures. (c) Higher magnification of the boundary between the internal fibrous layer and nacre in Nautilus belauensis. (d) Limit between nacre and external fibrous layers in Nautilus belauensis. (external prismatic: ep; n: nacre and internal and external fibrous layer: if, ef, respectively).

SEM views of the analysed thin sections. ( a ) Psilunio littoralis shell ...

Published: 01 February 2008
microstructures. ( c ) Higher magnification of the boundary between the internal fibrous layer and nacre in Nautilus belauensis . ( d ) Limit between nacre and external fibrous layers in Nautilus belauensis . (external prismatic: ep; n: nacre and internal and external fibrous layer: if, ef, respectively).
Image
Images of modern nacre for comparison with the fossil material. A, B) Gibbula cineraria, treated with Mutvei's protocol (Mutvei 1977). C, D) Nautilus pompilius, treated with bleach for a few minutes. E, F) Pinctada margatifera, treated with Mutvei's protocol. Scale bars: A,B,E–R = 2 μm; C, D = 200 nm.

Images of modern nacre for comparison with the fossil material. A , B ) ...

Published: 09 October 2018
Fig. 6.— Images of modern nacre for comparison with the fossil material. A , B ) Gibbula cineraria , treated with Mutvei's protocol ( Mutvei 1977 ). C , D ) Nautilus pompilius , treated with bleach for a few minutes. E , F ) Pinctada margatifera , treated with Mutvei's protocol. Scale
Image
Results from Electron Backscatter Diffraction (EBSD) analysis of nacre within the orthocerid cephalopod LACMIP 14793 from the Buckhorn Asphalt. A–D and E–H represent distinct regions of the inner surface of the shell wall. Rectangle in C shows the region that was analyzed via EBSD, producing the crystal orientation map in B and pole figure in D. Pole figures D and H show the clusters of orientations of the c (001), a (100), and b (010) axes of aragonite. The c axis is roughly vertical in all cases. Scale bars: A–C, E–G = 2.5 μm.

Results from Electron Backscatter Diffraction (EBSD) analysis of nacre with...

Published: 09 October 2018
Fig. 8.— Results from Electron Backscatter Diffraction (EBSD) analysis of nacre within the orthocerid cephalopod LACMIP 14793 from the Buckhorn Asphalt. A–D and E–H represent distinct regions of the inner surface of the shell wall. Rectangle in C shows the region that was analyzed via EBSD
Image
SEM photomicrographs of the shell microstructure. A) Outer aragonitic nacreous layer and thicker inner prismatic shell layer of Actinoceramus nipponicus. B) Sciponoceras glaessneri showing unaltered, stacked nacreous tablets and the absence of dissolution features, such as rounded tabulae, pits, or holes.

SEM photomicrographs of the shell microstructure. A) Outer aragonitic nacre...

Published: 01 September 2012
FIGURE 3— SEM photomicrographs of the shell microstructure. A) Outer aragonitic nacreous layer and thicker inner prismatic shell layer of Actinoceramus nipponicus. B) Sciponoceras glaessneri showing unaltered, stacked nacreous tablets and the absence of dissolution features, such as rounded tabula
Image
Nacre in abalone shell (left) and scanning electron micrograph (right) showing the nanoscale ordering of nacre components. From Darder and Ruiz-Hitzky (2007); reproduced with permission of The Clay Minerals Society

Nacre in abalone shell ( left ) and scanning electron micrograph ( right ) ...

Published: 01 April 2009
F igure 4 Nacre in abalone shell ( left ) and scanning electron micrograph ( right ) showing the nanoscale ordering of nacre components. F rom D arder and R uiz -H itzky ( 2007 ); reproduced with permission of T he C lay M inerals S ociety
Image
Microboring in nacre of a Mytilus edulis experimental shell exposed at the sediment-water interface in a reef environment for 1 yr, showing degree of shell degradation as a result of bioerosion. Scale bar is 50 μm.

Microboring in nacre of a Mytilus edulis experimental shell exposed at th...

Published: 01 July 2007
Figure 3. Microboring in nacre of a Mytilus edulis experimental shell exposed at the sediment-water interface in a reef environment for 1 yr, showing degree of shell degradation as a result of bioerosion. Scale bar is 50 μm.
Image
SEM micrograph of red abalone nacre tiles seen at a fractured edge.

SEM micrograph of red abalone nacre tiles seen at a fractured edge.

Published: 01 January 2005
Figure 14. SEM micrograph of red abalone nacre tiles seen at a fractured edge.