Unpatented mines and mining claims shall be exempt from taxation, but nothing in this section shall be so construed as to:
1. Exempt from taxation possessory claims to the public lands of the United States or of this state, or improvements thereon, or the proceeds of the mines; and
2. Interfere with the primary title to the lands belonging to the United States.
[Part 1:344:1953; A 1954, 29; 1955, 340]