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AUTHOR INFORMATION

MARCO LEONA, scientist-in-charge of the newly formed science group at the Metropolitan Museum of Art, New York, holds an M.S. in chemistry and a Ph.D. in mineralogy and crystallography from the University of Pavia, Italy. His main area of interest is the development of noninvasive analytical techniques for the study of works of art and artists' materials. This article was written when he was senior conservation scientist at the Los Angeles County Museum of Art. Address: Metropolitan Museum of Art, 1000 Fifth Ave., New York, N.Y. 10028; e-mail: marco.leona@metmuseum.org

FRANCESCA CASADIO received her Ph.D. in chemistry from the Universit� degli Studi di Milano, Italy. She was graduate intern in the Science Department at the Getty Conservation Institute, Los Angeles, then research fellow at the ICVBC-CNR “Gino Bozza” in Milan. Since July 2003 she has been conservation scientist at the Art Institute of Chicago. Address: Art Institute of Chicago, 111 South Michigan Ave., Chicago, Ill. 60603-6110; e-mail: fcasadio@artic.edu MAURO BACCI is director of research at the Institute of Applied Physics “Nello Carrara” IFAC-CNR, Florence. His main interest is in spectroscopy from both a theoretical and an applied point of view. For many years he has been developing totally nondestructive spectroscopic techniques for the study of works of art. Address: Institute of Applied Physics “Nello Carrara” IFAC-CNR, Via Panciatichi 64, 50127 Firenze, Italy; e-mail: m.bacci@ifac.cnr.it

MARCELLO PICOLLO is a researcher at the Institute of Applied Physics “Nello Carrara” IFAC-CNR, Florence, who has been working on spectroscopic investigations of works of art since 1991. His main focus is on pigment characterization using totally nondestructive spectroscopic, imaging, and x-ray techniques. Address: as for Bacci; e-mail: m.picollo@ifac.cnr.it