limestone vs quicklime

limestone

noun
  • Pertaining to or made of limestone. 

  • An abundant rock of marine and fresh-water sediments; primarily composed of calcite (CaCO₃); it occurs in a variety of forms, both crystalline and amorphous. 

quicklime

noun
  • Calcium oxide, which is produced by heating (calcining) limestone and gives slaked lime on treatment with water. 

verb
  • To treat with quicklime. 

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