Silver Ore Farming
Forest regions at 25+ seems pretty solid. Jump on the map run around looking for mines, farm, leave map (only if there are no other players with you to run the mission), rinse and repeat. Made 30 – 40 silver ore in an hour over 4 runs.
Expeditions, Encampments, Survivor Rescue rewards, in-world Chests.
It’s great to stumble upon a silver node in a mine, but hunting these out is much more frustrating than the above methods. Consider them a bonus, rather than the purpose IMO. Using the above methods also has the side-benefit of getting you much more swanky loot (Target for drops of rain/survivor XP to make your progression process much more smooth).
The most consistent drop of it is to finish an Outlander’s llama completely in 19-(whatever number is before 34, cause 34 drops malachite) missions. Encampment clears are probably the 2nd best bet. Though they only drop ore for the trigger person I think.