The monogram chips you show are not "crest and seal" chips. They are die cut monogram chips, or inlaid chips. While there was no trade association back then to standardize these terms, the term "crest and seal" (or variations like "seal and crest") were used with a great deal of consistency in the gambling supply catalogs.

Crest and Seal chips must have three characteristics;
(a) clay chip
(b) flat plain mold (that is, not an embossed rim mold)
(c) litho inlays (that is, round solid inlays that are printed on or written on)

I just looked quickly through Howdy Herz' "Harvey's Guide to Collecting Gaming Checks and Chips." Very nice book. I particularly like its 57 pages of reproductions of gambling supply catalogs (from the 1930's, 40's, 50's about). "Crest and Seal" (or Seal and Crest, etc.) was mentioned on pages B-10, 15, 23, 28, 41, 43 and 56. In all cases the chips were what I would, also, call crest and seal chips. They were all clay chips with a litho inlay and a flat (unembossed) mold. (Actually one or two may have had embossed rim molds, but that is not the issue here.)

So, the key thing is that Crest and Seal chips have round (99.999% of the time they are round) solid inlays that are printed on or written on (that is the "litho" part). [They also must be clay with a flat mold (that is, they must not have an embossed rim mold). No one argues those two points.] Crest and Seal chips are not like those pictured below -- with cut-up plain inlays. Those are called regular inlaid chips or die cut inlaid chips. In fact, in the gambling supply catalogs in "Harveys Guide.....", referred to above, the regular (non-crest and seal) inlays were called Wheel Checks or Inlaid Initial Checks or regular inlaid chips.

I find it unfortunate that Howdy calls any inlaid chip (litho inlay or die cut inlay) on a plain mold chip a Crest and Seal chip. He should read his own book.

For more pictures look at:
http://community-2.webtv.net/tds4chips/COLLECTINGGAMBLING/
http://www.antiquegamblingchips.com/uspc.htm

Robert