cast iron vs chalybeate

cast iron

adj
  • Made of cast iron. 

  • Inflexible or without exception. 

  • Durable; tough; resilient. 

noun
  • A hard and brittle, but strong, alloy of iron, carbon, and silicon, formed by casting in a mould. 

chalybeate

adj
  • Containing dissolved salts of iron. 

  • Tasting of iron, said of mineral water. 

noun
  • A mineral water containing iron, a voguish general remedy during the 17th-19th century. 

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