The following criminal offences raise particular concerns for freedom of expression
Scope of criminal liability.
A person incurs inchoate criminal liability when he incites another person to commit a crime, either incitement or solicitation. Advocacy of crime in the abstract also incurs criminal liability. All of them may result in criminal liability even if the crime they were intended to bring about does not materialize. Thus, the crime of incitement is committed in the public forum when poster encourages destruction of public property such as "a chunk of rich ore you chipped off the ledge sitting in your hand". Those who publicly support such statements could also be charged with the same offence as co-defendants.
Federal law says up to 10 years in prison for Incitement to commit a property crime.
Arizona law states: Damage or removal of natural rocks, vegetation, or public property is prohibited, thus rockhounding on public property, however, is more complicated as no damage can be occurred and area must be restored to natural state.
Chipping off a chunk of ore from its mother rock is a crime.
Mineral and Rock Collecting on the National Forests - Forest Service
Assume personal responsibility to notice if the area may indeed contain archaeological or historical resources and if it does, cease metal detecting and notify a Forest Service office. Not doing so may result in prosecution under the Code of Federal Regulations or ARPA.
https://www.fs.usda.gov/Internet/FSE_DOCUMENTS/stelprdb5261774.pdf