A Buddhist mural dated to around the seventh century A.D. is one
of many in Afghanistan's Bamian Valley that were recently found
to contain oil- and resin-based paints. The use of the
substances at such an early date is a surprise, since they
require sophisticated knowledge of chemical properties,
scientists say. Oil is used in paints to help fix dyes and help
them adhere to surfaces. It also changes a paint's drying time
and viscosity. Europeans began using oil in their pictures by
about 800 A.D., but the new research on the Central Asian pushes
back the onset of oil-based painting by at least a hundred
years. Researchers hope to find even earlier examples by
studying other Central Asian sites.
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