I don't recall seeing a Nevada chip designated as a "Marker" before. Do you suppose this was to facilitate a short term advance to the player when he "goes light" on a bet? Maybe like modern casinos do with a lammer placed on the table in the spot that designates the player getting the advance?

If the $5 chip was the only one so marked these were for very low stake games.

I understand Jesse Beck ran the Pan Games at Harolds Club before moving the game and chips to the Riverside later. These chips only said Pan on each side, and had no initials or casino name on them. Supposedly, the pan chips were drilled for the move so there was no further obligation of the Smiths to redeem them, while they could still be used (at least for a while) at Riverside.