'Boulders' in the Bible

"Moreover, a man or a woman who has a ritual spirit or a familiar spirit is certainly to die. They are to be stoned to death with boulders. They will continue to bear responsibility for their guilt."

So Moses spoke to the Israelis and they brought the one who cursed outside the camp and stoned him to death with boulders. The Israelis did just as the LORD had commanded Moses.

Then all the men of his city are to stone him with boulders so that he dies. This is how you will remove this evil from among you. Then all Israel will hear of it and will be afraid."

they are to bring her to the door of her father's house. Then the men of the city are to stone her with boulders until she dies for doing a detestable thing in Israel acting like a prostitute while in her father's house. By doing this, you will remove this evil from among you.

piling up a large mound of boulders that remains to this day. After this, the LORD turned his burning anger away, and that is why that place is called "the Valley of Achor" to this day.