Carved stone balls

Carved stone balls are curious type of artifact found at a number locations in Scotland. There are several theories that describe there use, however the lecture material disagrees with the reading material.
First, although the reading claims the carved stone balls were weapons used in hunting or fighting, the professor says if used in hunting or fighting, stone balls would break in pieces or crack, so they wouldn't be round in shape.
Second, the speaker refutes the reading by mentioning the stone ball's weight. Though our article states the carved stone balls were used as part of a primitive system of weights and measures, the professor argues that they were carved from several types of stone. Diffferent types of stone have different densities, so they will have a different weight. It is impossible to measure quantities of grain or other food on a balance of trade.
Third, while the article indicates the carved stone balls served a social purpose as opposed to a practical or utilitarian one. The speaker points out that most of the patterns are too simple to be seen as elaborate designs. Furthermore high status people would bury their stuff with them however the stone balls have not been found in the tombs or graves of those people.