I suppose most people have Ounce scales, and I know some of the more accurate, like my old triple-beam will do grams just fine.

Why would you use carats for chips. Accuracy or may I guess, because you have a scale that measures in that unit?

Don't the Mfgs. use Grams for their specifications and in their sales literature?

By the way, chips from the same casino, with the same mold and design, but different colors, have different weights. I think my red chips are heavier than the white chips from Red Cliff, Horse Head Right.

I see the chip weights as a close aproximation in most cases and not a precise measurement.

Used chips weigh less than the same chips do in new condition...

Answering how much does a casino chip weight is not going to have a simple finite answer.