I'm talking about the c&s with the holes punched in the inlay: Club St. Denis, West End Club, Elks Club #357, Beaver Club, etc. All these early USPC chips, besides having the small holes in the inlay for better adhesion, also had the protective coating. It wasn't one or the other. It had both.

Now the POW, crown, shield, flags, star & wreath, etc. chips are a different story. I don't consider them crest and seals. They are litho inlays.

The florida palms, sailing ship, spaniel, smoking arab, arab on a horse, etc. are crest and seals.

I do admit that the distinction tends to blur. The Burt company made seal & crests for a couple of years but over time reduced the amount of protective coating until in the '70s you got chips like the Sahara-Tahoe roulettes -- definitely not seal & crests.

Burt chips, in my opinion, devolved in 3 stages: 1st - seal and crests such as "Marine Club", "LKW", "Durkn & Urich", "SPAR", "Sportsman", etc. 2nd stage - semi-seal & crest such as Flamingo, Dunes, Great Provider, Pals Club. 3rd stage - litho inlays such as Harvey, Sahara-Tahoe, Barneys, Nugget, Prima Donna, Sharkeys, etc.

BTW I also think that USPC went through 3 stages: 1st: almost paste-ons with great graphics like the "Annona Cigar" and "Tod Sloane". Crest and seals (modest graphics) with the holes puched in the inlays and 3rd: crest and seals with the solid inlays.