Genesis 23:15-16

23:15 “Hear me, my lord. The land is worth 400 pieces of silver, but what is that between me and you? So bury your dead.”

23:16 So Abraham agreed to Ephron’s price and weighed out for him the price that Ephron had quoted in the hearing of the sons of Heth – 400 pieces of silver, according to the standard measurement at the time.