In 1993, the painting was examined by the McCrone Research Institute in Chicago. The findings of the evaluation from Dr. Walter C. McCrone confirmed that the painting was made before the Indian Ink Drawing created in 1955. Among the scientific tests that the McCrone Research Institute performed to make this determination were pigment testing, carbon dating, and evaluation of the Kodak slides.
Dr. Walter C. McCrone's determination was that the painting was undeniably done by Picasso - dedicated to the pilot - prior to 1955.
Dr. Walter C. McCrone
Walter Cox McCrone (1916-2002) was an American chemist who was considered a leading expert in microscopy. He was best known for his work on the Shroud of Turin, the Vinland map, and Forensic science.
McCrone received a bachelor's degree in chemistry (1938) and a Ph.D. in organic chemistry (1942), from Cornell University, after which he completed two years of post-doctoral work there. From 1944 to 1956 he was a microscopist and materials scientist at what is now the Illinois Institute of Technology.
Becoming an independent consultant in 1956, he founded McCrone Associates, an analytical consulting firm now located in Westmont, Illinois. In 1960, he founded the McCrone Research Institute, a nonprofit organization for teaching and research in microscopy and crystallography.
For more than thirty years he edited and published The Microscope, an international quarterly journal of microscopy. He also wrote more than 600 technical articles along with sixteen books or chapters. He is credited with expanding the usefulness of the microscope to chemists, who had previously considered it to be primarily a tool for the biologist. In 2000, the American Chemical Society presented him with its National Award in Analytical Chemistry.