ectype vs rubbings

ectype

noun
  • A copy, reproduction; especially as contrasted with the original, archetype, or prototype. 

  • An object in relievo or embossed. 

  • An idea or impression that corresponds to external reality. 

  • An impression (in wax, clay, &c.) of a seal or medal. 

rubbings

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