cleave vs mezzotint

cleave

noun
  • Flat, smooth surface produced by cleavage, or any similar surface produced by similar techniques, as in glass. 

verb
  • To make or accomplish by or as if by cutting. 

  • Followed by to or unto: to adhere, cling, or stick fast to something. 

  • To split. 

  • To split (a complex molecule) into simpler molecules. 

  • Of a crystal, to split along a natural plane of division. 

  • To break a single crystal (such as a gemstone or semiconductor wafer) along one of its more symmetrical crystallographic planes (often by impact), forming facets on the resulting pieces. 

  • To split or sever something with, or as if with, a sharp instrument. 

mezzotint

noun
  • A form of intaglio etching in which a metal plate is roughened evenly and then smoothed to bring out an image. 

  • An etching or print made using this method. 

verb
  • To make such etchings 

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