Planning a trip
Updated
The part that decides whether the day is legal, and the part people often skip.
Settle the land question first
Before anything else: who manages the ground, and what do they allow.
The answers differ by agency and sometimes by parcel. BLM land is generally the most permissive, with collection of reasonable amounts of rocks, mineral specimens and semiprecious gemstones allowed for noncommercial purposes. National Park Service land is the opposite: 36 CFR 2.1 prohibits removing mineral or paleontological specimens except as specifically authorized.
Forest Service land, state land, tribal land and private land each have their own answer, and a map showing "public land" does not tell you which.
What to find out
The managing agency for the exact parcel, not the general area.
Whether there is an active mining claim, which excludes collection even on otherwise open ground.
Whether the mineral estate is privately owned, which happens under public surface.
Whether it is a developed recreation site, a withdrawal or a special-use area.
And for private land, who owns it and whether you have permission in a form you could show somebody.
Season and weather
Access roads, which decide most trips in mountain country.
Heat, which is the actual hazard in desert collecting and kills people every year.
Flash flood risk in washes, which is where a lot of good material is.
And daylight, because the last hour is when tired people take risks on loose ground.
What to take
Water, more than you think. Then the notebook, which is the thing this whole property turns on.
Tell somebody where you are going and when you will be back. Collecting areas have no signal and loose ground.