Trey Wallace, age 9, of Charlotte, N.C., for his question:

WHAT EXACTLY IS INTAGLIO?

Intaglio is a form of engraving in which designs are hollowed out from the surface of the background. It is the opposite of the form of engraving in which the design stands higher than the background, or in relief. But, like relief engraving, intaglio serves as decoration, for inscriptions, or as a means of printing.

Intaglio forms of printing include some engraving, etching and rotogravure. Intaglio printing leaves the ink raised on the paper. In manufacturing, the term refers to a design hollowed out for use as a mold. Intaglio also is a design that is carved so that it is depressed below the surface.  Many gems are carved in intaglio.