lead crystal vs windowpane

lead crystal

noun
  • cut glass made of this material. 

  • glass that contains at least 24% lead oxide (PbO). 

windowpane

noun
  • A piece of glass filling a window or a section of a window 

  • A gelatin base tab with LSD. 

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