lithoglyph

from The Collaborative International Dictionary of English v.0.48

lithoglyph \lith"o*glyph\ (l[i^]th"[-o]*gl[i^]f), n. [Gr.
   liqoglyfi`a; li`qos stone + gly`fein to engrave.]
   An engraving on a gem.
   [1913 Webster]