How To Distinguish Cheating Dice
The easiest way to spot loaded dice is to fill a tall glass with water and then drop one of the dice into the water. Be gentle and hold the die close to the water before dropping it. If the die turns over as it goes down, then it is probably loaded. Try dropping the die several times, with a different face pointing upward each time. If a couple of numbers come up more often than the others, then you have probably got some loaded dice in your hands.
Legitimate dice should land evenly in the bottom of the glass.
Spotting beveled dice is easy too. Just hold the two dice together and see if they wobble. The dice should rest flush against each other and not wobble.
Flats are harder to detect, but you could easily take a pair of dice that are not crooked and compare them by holding them next to each other. Look for sides that are noticeably shorter than the others. Hope it will help you to recognized such devices!