Hadean vs inky

Hadean

name
  • The Hadean eon; part of the Precambrian supereon, spanning from around 4.6 to 4 billion years ago. 

adj
  • Pertaining to Hades or hell. 

  • Of, or relating to the geological eon. 

inky

adj
  • Of the colour of ink, especially black ink; dark. 

  • Spattered or stained with ink. 

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