unspoken vs mute

unspoken is not a noun while mute is a noun.

Word	Noun	Adjective	Verb	Adverb
unspoken	No	Yes	No	No
mute	Yes	Yes	Yes	No

As adjectives, unspoken and mute are synonyms defined as:

Other synonyms of unspoken include silent, tongueless, wordless.

unspoken (noun)	mute (noun)
	a device used to soften the tone of a musical instrument
	a deaf person who is unable to speak

unspoken (adjective)	mute (adjective)
not made explicit	expressed without speech
expressed without speech	unable to speak because of hereditary deafness

unspoken (verb)	mute (verb)
	deaden (a sound or noise), especially by wrapping