First, Steve, great pic.
Second, I too think you are entitled to a definition of a crest and seal.
Third, Robert's explanation is helpful but not complete.\
Fourth, JOHN BENEDICT, we need you to weigh in on this one and post a pic of a nice inlay side by side with a crest and seal inlay.
Fourth, and in the meantime, Steve, here is what Dale Seymour says about these chips. [Page 15, Antique Gambling Chips, Revised Ed.]:

"One popular, hig-qulity chip taht appeared about the turn of the century was called the Crest and Seal chip. Other mufacturers later called it the Crest or Seal and the Seal and Crest. As one ad stated, 'The design in Seal and Crest Checks is printed on the reverse side of a transparent celluloid inlay which prevents discoloration and wear of the design.' Crest and Seal cips could be custom made for anyone in any design the customer chose."