225 ILCS 710/36
No youth under the age of 18 shall be permitted to do any manual labor in or about any mine, and before any youth can be permitted to work in any mine an affidavit from his or her parent or guardian or next of kin, sworn and subscribed to before a notary public, that the youth is 18 years of age shall be given to the mine manager or operator.
The parent, guardian or next of kin shall submit in connection with such affidavit a certificate of birth, a baptismal certificate, a passport or other official or religious record of the youth's age or duly attested transcript thereof, which certificate or transcript thereof shall, for the purposes of this Act, establish the age of the youth.
Any person swearing falsely in regard to the age of a youth shall be guilty of perjury, and shall be punished as provided by law for that offense.
225 ILCS 710/36