asset vs mother lode

asset

noun
  • A thing or quality that has value, especially one that generates cash flows. 

  • A woman's breasts or buttocks or a man's genitalia. 

  • Coordinate term: liability 

  • Any component, model, process or framework of value that can be leveraged or reused. 

  • An intelligence asset. 

  • Any item recorded on the left-hand side of a balance sheet. 

mother lode

noun
  • Any source of valuable or useful material. 

  • A large or rich vein of gold or of another precious mineral from which other branches extend. 

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