The art of engraving gemstones, making intaglio and cameos. Stones are engraved using grindstones with powdered emory or diamond as an abrasive. Found on http://www.encyclo.co.uk/local/22290
Glyp·tog'ra·phy noun [ Greek ... carved + -graphy : confer French glyptographie .] The art or process of engraving on precious stones. [ R.] Found on http://www.encyclo.co.uk/webster/G/38