This is what the PDF for the USFS says about:
" Amateur Prospectors
In recent years, as full-time professional prospectors have almost disappeared from the
scene, amateur prospectors have become far more numerous. To many outside of the mining business it is difficult to distinguish between the two. The publicity, sometimes highly distorted, given to rushes such as the uranium boom of the 1950’s, the convenience of modern off-road vehicles, and the increasing amount of leisure time available to so many, have combined to produce tens of thousands of amateur prospectors. Some of these individuals make great efforts to equip and train themselves, and they are capable of finding prospects worthy of exploration and development.However, the majority of the amateurs are poorly motivated and so lacking in the most rudimentary knowledge that they create difficulties for those seriously engaged in prospecting and exploration. The amateur’s common lack of consideration for the rights of land owners, his abuse of laws and regulations, and his ill-conceived bulldozing of the surface have become so offensive that there is mounting pressure for drastic restrictions on all prospecting and exploration activities. A great deal of wisdom and fine judgment will be required in finding ways to regulate the recreationist prospector while not unduly restricting serious prospectors and geologists upon whom the Nation depends for future mineral discoveries."
Bejay