At least those have a weave mold so you can tell there is something odd about them.

How about these 2 Bellagio chips, which is fake and which is real?

Real is blue and fake is purple (which in real life appears to be deep blue, has slightly less sharp edges).

But unless you have them side by side you can never be assured of the color. Slightly fancier printing on the real with a black shadow on the 1 and $.