donation vs widow's mite

donation

noun
  • A voluntary gift or contribution for a specific cause. 

  • The act of giving or bestowing; a grant. 

widow's mite

noun
  • A very small gift or donation which, however, represents a great sacrifice on the part of the giver. 

  • The lepton coin. 

How often have the words donation and widow's mite occurred in a corpus of books? (source: Google Ngram Viewer )