County stadium district bonds issued under this article are securities in which public officers and bodies of this state and of municipalities and political subdivisions of this state, all companies, associations and other persons carrying on an insurance business, all financial institutions, investment companies and other persons carrying on a banking business, all fiduciaries and all other persons who are authorized to invest in obligations of the county may properly and lawfully invest. The bonds are also securities which may be deposited with public officers or bodies of this state and municipalities and political subdivisions of this state for purposes which require the deposit of state or county bonds or obligations.