This is just an awesome find. From the European Synchotron Radiation Facility:
"Opaque amber accounts for up to 80% of the amber found in Cretaceous sites like those in Charentes. From the outside, it is impossible to tell whether something may be contained inside. Malvina Lak and her colleagues from the University of Rennes and Paul Tafforeau of the ESRF, together with the National Museum of Natural History of Paris, have applied a synchrotron X-ray imaging technique known as propagation phase contrast microradiography to the investigation of opaque amber. This technique permits light to reach the interior of this dark amber, which resembles a stone to the human eye. “Researchers have tried to study this kind of amber for many years with little or no success. This is the first time that we can actually discover and study the fossils contained within”, says Paul Tafforeau.
The scientists imaged 640 pieces of amber from the Charentes region in south-western France. They discovered 356 fossil animals, ranging from wasps and flies, to ants and even spiders and acarians. The team was able to identify the family for 53% of the inclusions.[...]"
"Examples of virtual 3D extraction of organisms embedded in opaque amber: a) Gastropod Ellobiidae; b) Myriapod Polyxenidae; c) Arachnid; d) Conifer branch (Glenrosa); e) Isopod crustacean Ligia; f) Insect hymenopteran Falciformicidae. Credits: M. Lak, P. Tafforeau, D. Néraudeau (ESRF Grenoble and UMR CNRS 6118 Rennes)."
Hat tip to Martin!