The only think I can recommend.
If it's gold you're after, note how higher conducive coins read on Nox.
You can disc these out realizing you'll likely miss some silver jewelry or coins.
But the clad except for nickels should not be dug much at all.
Less scooping/ digging to put odds in your favor on gold.
Sensitivity on Nox doesn't have to be run real high either, especially on lower conductors.
It'll get down there.
No need for low (slower) speed setting either.
5,6 or 7 should do nicely.
Personally I would be interested in targets reading 7-17 on the meter. Lots of rings should be in this range. Bigger class rings you might miss. 7-19 would likely capture some of these. But the zincolns will be trying to creep in.
Best of luck.