Having been there and witnessed the amount of mining that has gone on in the past (150 yrs of mining activity/history) most of their gold seems to be in old river washes buried 100's of years ago .... the most efficient way of extracting that is, as seem on the Gold Rush shows, by removing the top soil layers to get down to the wash layers, then using the best available sluicing methods to extract it. Their gold is mostly finer alluvial gold .... not the large nuggets we dream of here.
Tony Beets does it with restored dredges .... much cheaper per ounce recovered and more efficient
Gold is panned from the rivers and creeks (have done that myself with some success) but not in amounts to warrant a professional operation.
Sluicing/panning is by far the most popular method, I assume because it's the most effective.
That being said there have been (very) limited finds of larger nuggets in old dredge tailings .... strangely probably because they were too large to be trapped in their sluices.
I'm sure that a detector would find gold amongst their diggings but again not the most efficient way of mining for them and, most of the areas are covered by leases. Detectors are used in the 'lower' states, Arizona/California etc etc ..... Garrett are a US detector maker and they are widely used over there (because they don't know any better).
The photos show the extent of their dreading, most of these were done pre 1940 .... certainly scares the landscape, there's mile upon mile of that type of scenery .... not pretty but pretty amazing.
Cheers Tom
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