Jeremiah 52:20-21

20The bronze from the things that King Solomon had made for the Lord's temple was very heavy. They included the two bronze pillars, the large bath called ‘the Sea’, the 12 bronze bulls under the bath and the carts which carried the buckets for water. The bronze from all these things was more than they could weigh.

21Each pillar was 8 metres high and 5 metres around. The bronze was 8 centimetres thick and each pillar was empty inside.