Inlay is a technique of fitting soil of a color different
from the base into the soil of the base.

In my work, The prototype is first shaped with iron riched clay,
and then line-engraving it,
then fill the gap left by the engraving with white soil,
The patterns on the surface are painted by using ceramics specialized pigments,
which renders extraodinarily colorful patterns.

In the interval of the inlaid line,
the pattern is painted with the color specially used for pottery.

To be exact: “This is a technique of mosaic coloring.”
So the job title uses “inlay”.