Exodus 30:13

13Each one who is numbered in the census shall give this: half a shekel
A  shekel was about 2/5 ounce or 11 grams
according to the bshekel of the sanctuary (the cshekel is twenty gerahs),
A  gerah was about 1/50 ounce or 0.6 gram
ehalf a shekel as an offering to the Lord.

Exodus 30:15-16

15The rich shall not give more, and the poor shall not give less, than fthe half shekel, when you give the Lord’s offering to make atonement for your lives. 16You shall take the atonement money from the people of Israel and shall ggive it for the service of the tent of meeting, that it may bring the people of Israel to hremembrance before the Lord, so as to make atonement for your lives.”

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