The following solid minerals shall not be subject to the tax imposed by this part:
(1) Solid minerals which are sold to governmental agencies in this state, including cities and counties.
(2) Solid minerals, except phosphate rock and heavy minerals, upon which the sales tax is ultimately paid to the state under chapter 212.
(3) Solid minerals which are extracted by the owner of the site of severance for the purpose of improving the site of severance, provided the site of severance is subject to a restoration or reclamation program which has been approved by the appropriate state or local governmental entity.
(4) Solid minerals, except phosphate rock, which are severed solely for direct application in agricultural uses.