Where in Jeremiah was Matthew refering to in Matthew 27v9?

Matthew 27:9 Then was fulfilled that which was spoken by Jeremy (where?) the prophet, saying, And they took the thirty pieces of silver, the price of him that was valued, whom they of the children of Israel did value; === === == The thirty pieces can be found in Zechariah 11:12-13 not in Jeremiah.

they weighed for my price thirty pieces of silver. And the LORD said unto me, Cast it unto the potter: a goodly price that I was prized at of them. And I took the thirty pieces of silver, and cast them to the potter in the house of the LORD.

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