The price
"And I said to them: If it be good in your eyes, bring hither my wages: and if not, be quiet. And they weighed for my wages thirty pieces of silver."
Zacharias (Zechariah) 11:12 · around 520 BC
Thirty pieces of silver was the price the Law set for a slave killed by an ox (Exodus 21:32). It was an insult, and God calls it one:
"And the Lord said to me: Cast it to the statuary, a handsome price, that I was prized at by them. And I took the thirty pieces of silver; and I cast them into the house of the Lord, to the statuary."
Zacharias (Zechariah) 11:13
"Statuary" is the Douay-Rheims word for a worker in clay: a potter.
So there are three details. Thirty pieces of silver. Thrown into the house of the Lord. Ending up with the potter.
The betrayal
"Then went one of the twelve, who was called Judas Iscariot, to the chief priests. And said to them: What will you give me, and I will deliver him unto you? But they appointed him thirty pieces of silver."
Matthew 26:14 to 15
Thirty, exactly the number Zechariah wrote down five hundred years before.
Where the money went
After Jesus was condemned, Judas tried to give the money back. The priests refused it:
"And casting down the pieces of silver in the temple, he departed and went and hanged himself with an halter. But the chief priests having taken the pieces of silver, said: It is not lawful to put them into the corbona, because it is the price of blood. And after they had consulted together, they bought with them the potter's field, to be a burying place for strangers."
Matthew 27:5 to 7
Thrown down in the house of the Lord. Spent on the potter. Every detail, carried out by men who had no intention of fulfilling anything.
Why this is a big deal
Judas didn't set the price. The priests did. And the priests didn't plan to buy a potter's field. They just didn't want blood money in the treasury.
Nobody involved was trying to match Zechariah. They matched him anyway, down to the last coin.