The two street facades are covered in terra-cotta.

Like many buildings in Pittsburgh, the museum's two street facades are coated in cream-colored glazed terra-cotta.

Terra-cotta was a popular surface embellishment at the turn of the century because of its decorative beauty and self-cleaning properties. Basically, terra-cotta has a layer of protective film which keeps its pores from absorbing water and dust. Because of the layer of film, rainwater easily washes away any dust on the surface.

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