Exodus 30:13World English Bible
They shall give this, everyone who passes over to those who are counted, half a shekel after the shekelA shekel is about 10 grams or about 0.35 ounces. of the sanctuary (the shekel is twenty gerahsa gerah is about 0.5 grams or about 7.7 grains); half a shekel for an offering to Yahweh.