I've picked apart a cracked Claridge Hi-Ho chip which is the same construction procedure as the Harrah's example. One can clearly see the underlying plastic center core (or mold). In this case it is green, which represents the green letters showing through the surface of the chip. The Harrahs example was a black center core.

So, if some $1 "Harrahs" appeared opposite each side vs. one side "Harrahs" and the other side of the mold "Marina Casino Hotel" that would indicate two different molds were used.... possibly two different orders (re-orders)?

Hope this helps explain it.