Desert varnish or rock varnish is an orange-yellow to black coating found on exposed rock surfaces in arid environments. Desert varnish is usually around one micron thick and present nanometre-scale layering. Rock rust and desert patina are other terms which are also used for the condition, but less often.
Read more about Desert Varnish: Formation, Composition
Famous quotes containing the words desert and/or varnish:
“Critical lice are like body lice, which desert corpses to seek the living.”
—Théophile Gautier (1811–1872)
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