incrustation vs incrust

incrustation is a noun but incrust is not a noun.

Word	Noun	Adjective	Verb	Adverb
incrustation	Yes	No	No	No
incrust	No	No	Yes	No

incrustation (noun)	incrust (noun)
a decorative coating of contrasting material that is applied to a surface as an inlay or overlay
a hard outer layer that covers something
the formation of a crust

incrustation (verb)	incrust (verb)
	form a crust or a hard layer
	cover or coat with a crust
	decorate or cover lavishly (as with gems)