Looks like there is one hashmark on each side of an arrowdie chip, at least mine. Each side has 12 dice (2 sets of 1 thru 6). So there are two one-spots (aces) on each side. On each side there is only one hashmark (looks like a slanted file mark) abvove (only) one of the one-spot dies. Same thing on the other side.

thanks again, Jim. I never knew all this till now..
Robt.