If you've got significant ground mineralization &/or electrical interference, you might want to use the DE(fault) mode, disc with best separation. Maybe threshold -1 sens 50-99, or threshold 0 sens 30-50, or threshold +1 sens 15-30. Something in this range should work almost anywhere.
Higher sens with 0 or +1 did not increase distance detected in air test. Higher sens makes audio less modulated. Lower sens will make deeper items give a softer beep.
With threshold negative, there is some depth loss with high disc. 0 or + threshold & there seems to be no depth loss turning up disc to reject pulltabs.
If you have low ground minerals but electrical interference, you may be able to use the SL mode (deeper but separation not as good) with a threshold of maybe -3 and sens 99 worked in air, but lower if ground noise.
For coin hunting, the IDs are pretty jumpy in bad ground. If it stays above pulltab on most passes, & sometimes reaches dime or quarter #s, dig it. In bad ground, nickels & pulltabs below 3" may ID as zinc. So you could probably still get deep gold rings while rejecting shallow tabs in bad ground.
If you have good ground, IDs should be accurate to impressive depths. I was able to get correct ID in air test with quarter to 12" inside house.
As for gold, like all detectors I can think of, ID all over. Small rings probably read as foil or nickel. Medium size rings pulltab, large rings maybe zinc #s or higher.
If ground is highly variable, ground rebalance frequently for best depth.
You might have the disc set about 15 if you want to dig all but iron to get gold jewelry. Here are some of my air tests inside house with a quarter-electrical interference present but of course no ground minerals, disc at 15:
DE -1 sens 60 9" DE 0 sens 30 9" DE +1 sens 15 9.5"* DE +2 sens 10 9"*
SL -7 sens 99 10" SL -5 sens 99 11" SL -3 sens 99 11.5" SL -1 sens 10 11.5"*
* indicates unstable due to electrical interference. But #s that are stable on ground may be higher than #s that are stable in air inside house, at least in DE mode. In bad ground, SL mode may not be usable. HH, George (MN)
