By slicing rocks very thin and using special filters, geologists can turn a drab-looking rock sample into a slice of color. These photographs zoom in on tiny sections of rock just a few millimeters across. The images can tell geologists about the formation and composition of a rock, or, as Italian geoscientist Bernardo Cesare discovered, they can provide a palette for artistic beauty.
Above, a sample of slag (a byproduct from smelting ore into metals) provided by Ivana Angelini. Read the full article.