John Skelton, The Poetical Works of John Skelton…
“ In our early poetry “white as whales bone” is a common simile; and there is reason to believe that some of our ancient writers supposed the ivory then in use (which was made from the teeth of the horse-whale, morse, or walrus) to be part of the bones of a whale. Skelton, however, makes a distinction between “whalis bone” and the real ivory (see v. 468) . The latter was still scarce in the reign of Henry the Eighth; but, before that period, Caxton had told his readers that “the tooth of an olyfaunt is yuorye.” ”
