Desert Varnish | Landscape Boulders in St. George, Utah

What is Desert Varnish?

Desert Varnish, also known as rock varnish, desert patina, or rock rust, is the popular term used to describe the naturally-occurring coating found on exposed rock surfaces in arid climates throughout the world. Desert varnish can range in color from various shades of brown to grey or black, depending on the ratio of elements found in the varnish. Iron oxide, for example, is responsible for the brownish-red coloring while manganese oxide creates the various shades of grey and black. Many other factors such as hardness, water permeability, precipitation, and pH levels, contribute to the creation of desert varnish.