insignificant vs insignificance

insignificant is not a noun while insignificance is a noun.

Word	Noun	Adjective	Verb	Adverb
insignificant	No	Yes	No	No
insignificance	Yes	No	No	No

insignificant (noun)	insignificance (noun)
	the quality of having little or no significance

insignificant (adjective)	insignificance (adjective)
devoid of importance, meaning, or force
signifying nothing
of little importance or influence or power; of minor status
small and unimpressive