Scientists from the Tokyo Research Institute for Cultural Properties in Japan, the Centre of Research and Restoration of the French Museums in France, the Getty Conservation Institute in the United States, and the European Synchrotron Radiation Facility (ESRF) in Grenoble, France, analysed samples from the paintings, typically less than 1 mm across. They discovered that the paint contained pigments such as vermilion (red mercury sulfide) and lead white (lead carbonate). These were mixed with a range of binders, including natural resins, gums (possibly animal skin glue or egg), and oils, probably derived from walnuts or poppies. Specifically, researchers identified drying oils from murals showing Buddhas in vermilion robes sitting cross-legged amid palm leaves and mythical creatures as being painted in the middle of the 7th century. It is believed that they are the oldest known surviving examples of oil painting, possibly predating oil painting in Europe by as much as six centuries. The discovery may lead to a reassessment of works in ancient ruins in Iran, China, Pakistan, Turkey, and India.