'Stone' in the Bible

And he went to his father's house at Ophrah, and slew his brothers the sons of Jerubba'al, seventy men, upon one stone; but Jotham the youngest son of Jerubba'al was left, for he hid himself.

and you have risen up against my father's house this day, and have slain his sons, seventy men on one stone, and have made Abim'elech, the son of his maidservant, king over the citizens of Shechem, because he is your kinsman--

Among all these were seven hundred picked men who were left-handed; every one could sling a stone at a hair, and not miss.