unyielding vs persistent

unyielding and persistent both are adjectives.

Word	Noun	Adjective	Verb	Adverb
unyielding	No	Yes	No	No
persistent	No	Yes	No	No

As adjectives, unyielding and persistent are synonyms defined as:

Other synonyms of unyielding include dogged, dour, pertinacious, tenacious.

unyielding (adjective)	persistent (adjective)
resistant to physical force or pressure	retained; not shed
stubbornly unyielding	never-ceasing
	stubbornly unyielding
	continually recurring to the mind