Chemistry of Archaeopteryx

A fossil specimen of the half-dinosaur/half-bird, archaeopteryx, has been placed under the X-ray beam at the Stanford Synchrotron Radiation Lightsource(SSRL). By recording how the X-rays interacted with the fossil, the scientists have been able to identify the precise locations of chemical elements hidden within. The concentration of elements in the fossil differs significantly from those in the surrounding rock, ruling out the possibility that the elements have leached from the surrounding rock into the fossil.

The results show that portions of the feathers are not just impressions of long-decomposed organic material as previously believed, but are actually fossilized feathers containing phosphorous and sulfur, the elements found in modern bird feathers. Trace amounts of copper and zinc have been found in the fossil's bones, just as in the bones of modern birds.

Reference:
U. Bergmann, R. W. Morton, P. L. Manning, W. I. Sellers, S. Farrar, K. G. Huntley, R. A. Wogelius, P. Larson. Archaeopteryx feathers and bone chemistry fully revealed via synchrotron imaging. Proceedings of National Academy of Sciences, 2010; DOI: 10.1073/pnas.1001569107