authentication vs hallmark

authentication and hallmark both are nouns.

Word	Noun	Adjective	Verb	Adverb
authentication	Yes	No	No	No
hallmark	Yes	No	No	No

As nouns, authentication and hallmark are synonyms defined as:

authentication and hallmark: a mark on an article of trade to indicate its origin and authenticity

Other synonyms of authentication include assay-mark.

authentication (noun)	hallmark (noun)
validating the authenticity of something or someone	a distinctive characteristic or attribute of someone or something
a mark on an article of trade to indicate its origin and authenticity	a mark on an article of trade to indicate its origin and authenticity