nonauthentic vs unreal

nonauthentic

adj
  • Not authentic. 

unreal

adj
  • Not real or substantial; having no actual presence in reality; lacking the characteristics of reality. 

  • very impressive; amazing; unbelievable; incredible; larger or more fantastic than typical of real life. 

How often have the words nonauthentic and unreal occurred in a corpus of books? (source: Google Ngram Viewer )