At least in Australia, the tin mine scenario would go like this: an exploration company would peg an exploration lease-the monopoly right to explore for minera

At least in Australia, the tin mine scenario would go like this: an exploration company would peg an exploration lease-the monopoly right to explore for minerals on that land. They pay the (state) government for the privilege. when an economic deposit is discovered, the company can apply for a mining lease-the monopoly right to exploit the tin deposit. The pay the government for the lease, and also a royalty on the minerals. Whilst you can say that the mine was not there, and someone had to invest capital to exploit the deposit, the minerals themselves were always there, and once extracted are gone forever. Perhaps the price at which the government sells monopoly mineral rights relative to the profits sets the boundary between rent seeking and not?