amulet vs conjuration

amulet

noun
  • A kind of protective charm or ornament, often bearing magical symbols, worn for protection against ill will, negative influences, or evil spirits. 

conjuration

noun
  • Conjuring, legerdemain or magic. 

  • A magic trick. 

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