chromaticity vs mottle

chromaticity

noun
  • An objective specification of the quality of a colour, regardless of its luminance. 

mottle

noun
  • A distinguishing blotch of color. 

  • A mottled coloration or pattern. 

verb
  • To mark with blotches of different color, or shades of color, as if stained; to spot; to maculate. 

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