Tyrian purple vs purpure

Tyrian purple

adj
  • Of a deep purple colour, tinted with red, like that of the dye. 

noun
  • A deep purple colour, tinted with red, like that of the dye. 

  • A deep purple dyestuff obtained from the bodies of mollusks of the genus Murex (now moved to the genus Haustellum). 

purpure

adj
  • In blazon, of the colour purple. 

noun
  • A purple colour on a coat of arms, represented in engraving by diagonal parallel lines 45 degrees clockwise. 

  • purpure 

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