Hostname: page-component-5db6c4db9b-s6gjx Total loading time: 0 Render date: 2023-03-26T01:11:36.089Z Has data issue: true Feature Flags: { "useRatesEcommerce": false } hasContentIssue true

Phase Contrast X-Ray Synchrotron Imaging: Opening Access to Fossil Inclusions in Opaque Amber

Published online by Cambridge University Press:  03 March 2008

Malvina Lak
European Synchrotron Radiation Facility, BP 220, F-38043 Grenoble Cedex, France Géosciences Rennes, UMR 6118, CS 74205, 35042 Rennes Cedex, France
Didier Néraudeau
Géosciences Rennes, UMR 6118, CS 74205, 35042 Rennes Cedex, France
André Nel
CNRS UMR 5202, Muséum National d'Histoire Naturelle, Entomologie, CP 50, F-75005 Paris, France
Peter Cloetens
European Synchrotron Radiation Facility, BP 220, F-38043 Grenoble Cedex, France
Vincent Perrichot
Museum für Naturkunde der Humboldt–Universität zu Berlin, D-10115 Berlin, Germany
Paul Tafforeau*
European Synchrotron Radiation Facility, BP 220, F-38043 Grenoble Cedex, France LGBPH Poitiers, UMR 6046, F-86022 POITIERS Cedex, France
Corresponding author. E-mail:
Get access


A significant portion of Mesozoic amber is fully opaque. Biological inclusions in such amber are invisible even after polishing, leading to potential bias in paleoecological and phylogenetic studies. Until now, studies using conventional X-ray microtomography focused on translucent or semi-opaque amber. In these cases, organisms of interest were visualized prior to X-ray analyses. It was recently demonstrated that propagation phase contrast X-ray synchrotron imaging techniques are powerful tools to access invisible inclusions in fully opaque amber. Here we describe an optimized synchrotron microradiographic protocol that allowed us to investigate efficiently and rapidly large amounts of opaque amber pieces from Charentes (southwestern France). Amber pieces were imaged with microradiography after immersion in water, which optimizes the visibility of inclusions. Determination is not accurate enough to allow precise phylogenetic studies, but provides preliminary data on biodiversity and ecotypes distribution; phase contrast microtomography remains necessary for precise determination. Because the organisms are generally much smaller than the amber pieces, we optimized local microtomography by using a continuous acquisition mode (sample moving during projection integration). As tomographic investigation of all inclusions is not practical, we suggest the use of a synchrotron for a microradiographic survey of opaque amber, coupled with microtomographic investigations of the most valuable organisms.

Biological Applications
Copyright © Microscopy Society of America 2008

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)



Baruchel, J., Lodini, A., Romanzetti, S., Rustichelli, F. & Scrivani, A. (2001). Phase-contrast imaging of thin biomaterials. Biomater 22, 15151520.Google Scholar
Beckmann, F., Bonse, U., Busch, F. & Günnewig, O. (1997). X-ray microtomography (μCT) using phase contrast for the investigation of organic matter. J Comput Assist Tomogr 21, 539553.Google Scholar
Cloetens, P., Barrett, R., Baruchel, J., Guigay, J.-P. & Schlenker, M. (1996a). Phase objects in synchrotron radiation hard X-ray imaging. J Phys D Appl Phys 29, 133146.Google Scholar
Cloetens, P., Ludwig, W., Baruchel, J., Guigay, J.-P., Pernot-Rejmánková, P., Salomé-Pateyron, M., Schlenker, M., Buffières, J.-Y., Maire, E. & Peix, G. (1996b). Hard X-ray phase imaging using simple propagation of a coherent synchrotron radiation beam. J Phys D Appl Phys 32, A145A151.Google Scholar
Cnudde, V., Bosselaers, J., Masschaele, B., Vlassenbroeck, J., Dierick, M., Van Hoorebeke, L. & Jacobs, P. (2006). Species description of fossil spiders supported by non-destructive high-resolution X-ray CT. Geophys Res Abs 8, 08351.Google Scholar
Dierick, M., Cnudde, V., Masschaele, B., Vlassenbroeck, J., Van Hoorebeke, L. & Jacobs, P. (2007). Micro-CT of fossils preserved in amber. Nucl Instrum Methods A 580, 641643.Google Scholar
Grimaldi, D., Nguyen, T. & Ketcham, R. (2000). Ultra-high-resolution X-ray computed tomography (UHR CT) and the study of fossils in amber. In Studies on Fossils in Amber, with Particular References to the Cretaceous of New Jersey, D. Grimaldi (Ed.), pp. 7791. Leiden, The Netherlands: Backhuys Publishers.Google Scholar
Henderickx, H., Cnudde, V., Masschaele, B., Dierick, M., Vlassenbroeck, J. & Van Hoorebeke, L. (2006). Description of a new fossil Pseudogarypus (Pseudoscorpiones: Pseudogarypidae) with the use of X-ray micro CT to penetrate opaque amber. Zootaxa 1305, 4150.Google Scholar
Hennig, W. (1971). Insektenfossilien aus der unteren Kreide. III. Empidiformia (“Microphorinae”) aus der unteren Kreide und aus dem Baltischen Bernstein; ein Vertreter der Cyclorrhapha aus der untere Kreide. Stuttgarter Beiträge zur Naturkunde (B) 232, 128.Google Scholar
Momose, A. (1995). Demonstration of phase-contrast X-ray computed tomography using an X-ray interferometer. Nucl Instrum Methods Phys Res A 352, 622628.Google Scholar
Néraudeau, D., Allain, R., Perrichot, V., Videt, B., De Lapparent de Broin, F., Guillocheau, F., Phillippe, M., Rage, J.C. & Vullo, R. (2003). Découverte d'un dépôt paralique à bois fossiles, ambre insectifère et restes d'Iguanodontidae (Dinosauria, Ornithopoda) dans le Cénomanien inférieur de Fouras (Charente-Maritime, Sud-Ouest de la France). C R Palevol 2, 221230.Google Scholar
Néraudeau, D., Perrichot, V., Colin, J.P., Girard, V., Gomez, B., Guillocheau, F., Masure, E., Peyrot, D., Tostain, F., Videt, B. & Vullo, R. (2008). A new amber deposit from the cretaceous (uppermost Albian-lowermost Cenomanian) of SW France. Cretaceous Res., in press.Google Scholar
Néraudeau, D., Perrichot, V., Dejax, J., Masure, E., Nel, A., Philippe, M., Moreau, P., Guillocheau, F. & Guyot, T. (2002). Un nouveau gisement à ambre insectifère et à végétaux (Albien terminal probable): Archingeay (Charente-Maritime, France). Geobios 35, 233240.Google Scholar
Perrichot, V. (2004). Early cretaceous amber from south-western France: Insight into the Mesozoic litter fauna. Geologica Acta 2, 922.Google Scholar
Perrichot, V. (2005). Environnements paraliques à ambre et à végétaux du Crétacé nord-aquitain (Charentes, Sud-Ouest de la France). Mémoires de Géosciences Rennes, 118, 310 pp.Google Scholar
Perrichot, V., Nel, A. & Néraudeau, D. (2007). Schizopterid bugs (Insecta: heteroptera) in mid-Cretaceous ambers from France and Myanmar (Burma). Palaeontology 50, 13671374.Google Scholar
Polcyn, M.J., Rogers, J.V. II, Kobayashi, Y. & Jacobs, L.L. (2003). Computed tomography of an Anolis lizard in dominican amber: Systematic, taphonomic, biogeographic, and evolutionary implications. Palaeontologia Electronica 5, 13 pp.Google Scholar
Snigirev, A., Snigireva, I., Kohn, V., Kuznetsov, S. & Schelokov, I. (1995). On the possibilities of X-ray phase contrast microimaging by coherent high-energy synchrotron radiation. Rev Sci Instrum 66, 54865492.Google Scholar
Tafforeau, P., Boistel, R., Boller, E., Bravin, A., Brunet, M., Chaimanee, Y., Cloetens, P., Feist, M., Hoszowska, J., Jaeger, J.-J., Kay, R.F., Lazzari, V., Marivaux, L., Nel, A., Nemoz, C., Thibault, X., Vignaud, P. & Zabler, S. (2006). Applications of X-ray synchrotron microtomography for non-destructive 3D studies of paleontological specimens. Appl Phys A Mater Sci Process 83, 195202.Google Scholar
Wilkins, S.W., Gureyev, T.E., Gao, D., Pogany, A. & Stevenson, A.W. (1996). Phase-contrast imaging using polychromatic hard X-rays. Nature 384, 335338.Google Scholar