"Imagine if you could see the pen Beethoven used to write his Symphony No. 5. Or the chisel Michelangelo used to sculpt his David. Art lovers find endless fascination in the materials of artists — a pen, a brush, even a rag can become sacred objects, humanizing a work of art."

"And now, at Washington, D.C.'s National Gallery of Art, visitors can see some of the materials that impressionist Mary Cassatt once used — three well-loved, large wooden boxes of pastels from distinguished Paris art supply stores. Each box is filled with stubby pieces of pastels, some worn down to half an inch, others almost untouched."