Leviticus 27:2-3

2Speak to the people of Israel and say to them, If anyone amakes a special vow to the Lord involving the valuation of persons, 3then the valuation of a male from twenty years old up to sixty years old shall be fifty shekels
A  shekel was about 2/5 ounce or 11 grams
of silver, according to the cshekel of the sanctuary.
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