Cleromancy

cle-ro-man-cy [kleer-uh-man-see, kler-] noun the casting of lots as a means of divination.

-dictionary.com

Cleromancy was an ancient practice of dropping stones, bones, pebbles, colored glass, ect. and watching how they landed. The way they landed gave answers to questions asked. This was practiced in Ancient Rome, China, and Egypt. The Chinese used two curved bamboo blocks. If both landed with the curve up it was a positive answer. If both curves were down it was negative. This is still practiced today.

The use of small stones in Cleromatic ways has been practiced all over the world. It is still used today to predict omens. All the pebbles or stones have to be the same size and smooth. Then you choose an equal number of light colored stones and an equal number of dark colored stones, preferably 13 of each. Keep them in a small bag and ask yes and no questions. Choose one stone out of the bag. If you choose a light colored stone the answer is yes, if dark the answer is no. Repeat the question several times, then take the average. If more light colored stones the answer is more than likely yes. Dice divination is derived from this practice.

- http://www.occultopedia.com/c/cleromancy.htm