ingot vs ore

ingot

noun
  • A solid block of more or less pure metal, often but not necessarily bricklike in shape and trapezoidal in cross-section, the result of pouring out and cooling molten metal, often immediately after smelting from raw ore or alloying from constituents. 

verb
  • To form (scraps of metal) into ingots. 

ore

noun
  • Rock or other material that contains valuable or utilitarian materials; primarily a rock containing metals or gems for which it is typically mined and processed. 

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