Sardonyx is used to cut cameos. When the original rough is parted along the lines instead of across them, it results in alternating layers of color. White or light colored material is oriented to the top and the darker color below. In the case of sardonyx, the white or cream color band is the upper most, and the orange or brown band is located below.

When the top (light colored band) is carved it begins to show the darker material below. Hence the shadows are created by letting the dark color show through.

The diagram to the left shows the general steps in creating a cameo type blank. Two layers of bands of agate remain.

The top band is then cut or carved to reveal the color below and this creates the pattern.