diaglyph 凹雕
凹刻
diaglyph[ noun ]
glyptic art consisting of a sunken or depressed engraving or carving on a stone or gem (as opposed to cameo)
<noun.artifact>
Diaglyph \Di"a*glyph\, n. [Gr. ? to engrave; dia` through + ? to
carve.]
An intaglio. --Mollett.