quicksilver vs unvarying

quicksilver

noun
  • The metal mercury. 

  • An amalgam of mercury and tin applied to the backs of mirrors, quicksilvering. 

verb
  • To overlay with quicksilver. 

  • To treat with quicksilver. 

adj
  • Unpredictable, erratic or fickle; mercurial. 

unvarying

adj
  • lacking variety; having a uniform character 

  • persistent, constant, changeless 

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