catlinite vs potter's clay

catlinite

noun
  • A red clay from the Upper Missouri region, used by the natives for their pipes. 

potter's clay

noun
  • The clay used by a potter. 

  • A person or people created and shaped by God. 

  • A nation or kingdom. 

How often have the words catlinite and potter's clay occurred in a corpus of books? (source: Google Ngram Viewer )