adobe vs pipeclay

adobe

noun
  • An unburnt brick dried in the sun. 

  • The earth from which such bricks are made. 

  • A house made of adobe brick. 

pipeclay

noun
  • catlinite 

verb
  • To whiten by application of pipeclay. 

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