coppery vs cupric

coppery

adj
  • Containing copper, especially if abundantly. 

  • Resembling the metal copper, especially in color. 

cupric

adj
  • Of, pertaining to, or derived from, copper; containing copper. 

  • Containing copper with an oxidation number of 2 

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