Gold placer claim
In the United States, a placer claim grants to the discoverer of valuable minerals contained in loose material such as sand or gravel the right to mine on public land. Other countries such as Canada, Mexico, and Australia grant similar rights. In the United States, the valuable mineral in a placer claim is almost always gold, although other nations mine placer deposits of platinum, tin, and diamonds. Another type of mining claim is a lode claim.
A mining claim allows some security of tenure for the owner, providing an incentive to invest time and money developing the deposit. Mining claim laws vary from state to state, but claims staked over federal minerals follow federal mining law. Federal minerals are managed by the U.S. Bureau of Land Management (BLM).
Mining claims staked under either State or federal laws (state claims may only be staked on state-owned and managed lands; federal claims may only be staked on minerals owned by the federal government) are limited to lands available for claim staking at the time the claims are staked. Thus, if the land is not available for mineral entry (example: withdrawn due to its status as a park or refuge), then the claim is said to be invalid ab initio. An additional requirement is "Discovery", which follows the "Prudent Man Rule." This means that a sufficient indication of valuable mineral(s) would encourage a "Prudent Man" to further invest time and money developing the deposit towards the goal of mining it. The holder of a mining claim does not own the surface, the water, or even the rocks and gravel. A mining claim grants the holder with the preferential right to extract the valuable minerals within the claim, and for uses incident to that goal, such as prospecting, exploration and development. Gold mining is one of the most common uses for the staking of mining claims.
In Alaska, state mining claims may be up to 160 acres (0.65 km2), and there is no distinction between lode or placer claims. The boundaries of the claim must follow the 4 cardinal directions, with an exception being adjustments for existing valid claims. "Claim jumping", which happens to this day, is a case where one person overstakes the claims of another. This results in civil action, and sometimes violence.
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