mettle vs resoluteness

mettle

noun
  • Good temperament and character. 

  • A quality of endurance and courage. 

adj
  • Spirited, vigorous, stout-hearted. 

resoluteness

noun
  • The state or characteristic of being resolute; determination or resolution. 

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