First, the passage claims that those carved stones were weapons that used in hunting and wars. Although, the professor opposes this by saying any kind of weapon should contains sign on it. On the other hand, this curved stones do not contain any signs on them. Moreover, if they were used as weapons, they were have cracks on them or some parts would be knocked off, but these were well preserved, with no damage at all.
Second, the article avers that they had been used in measurement and weight.