'Shekels' in the Bible

And when he cut the hair of his head (now it was at every year's end that he cut it; because it was heavy on him, therefore he cut it); he weighed the hair of his head at two hundred shekels, after the king's weight.

and Ishbibenob, who was of the sons of the giant, the weight of whose spear was three hundred'shekels of brass in weight, he being girded with a new'sword , thought to have slain David.

And the king said unto Araunah, Nay; but I will verily buy it of thee at a price. Neither will I offer burnt-offerings unto Jehovah my God which cost me nothing. So David bought the threshing-floor and the oxen for fifty shekels of silver.