'Half shekel' in the Bible

This is what everyone who is counted shall give [as he joins those already counted]: a half shekel, according to the sanctuary shekel (the shekel is twenty gerahs); a half shekel as a contribution to the Lord.

When they arrived in Capernaum, the collectors of the half-shekel [temple tax] went up to Peter and said, “Does not your teacher pay the half-shekel?”