loam vs pipestone

loam

noun
  • A mixture of sand, clay, and other materials, used in making moulds for large castings, often without a pattern. 

  • A type of soil; an earthy mixture of sand, silt and clay, with organic matter to which its fertility is chiefly due. 

adj
  • Made of loam; consisting of loam. 

verb
  • To cover, smear, or fill with loam. 

pipestone

noun
  • A hard, red clay used by Native Americans for making tobacco pipes. 

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