MtnBluBrd, I feel your pain

All too often the "recipe" given for finding jewelry on these forums, is to "turn down the disc. all the way down, to only reject iron, and go to junky parks, and dig till your arms fall off". This admonition is nothing but a recipe for torture! Oh sure, gold rings tend to read down low, and yes, if you knock out foil and tabs, yes you'll also knock out gold rings. But this is only a small portion of the recipe!
The rest of the formula should be in choosing the right spots, where jewelry ratios are higher TO BEGIN WITH! And junky blighted inner city urban park turf, is NOT the place to "be a hero" and try to dig gold rings from the mass of aluminum shrapnel. I know of parks where the ratio would be multiple hundreds of aluminum, to any one gold ring. Simply not worth it.
The best place to find jewelry, is swimming beaches. Either lakes or ocean beaches. Because think of it: a) people frolicking around in cooler waters, which shrink fingers. b) people lathering up with slippery suntan lotion (which lets jewelry slip off easier) c) people frolicking around pitching frisbees, volleyballs, etc... with their arms flailing about d) people in un-natural "prone" positions, as they lie flat on beach blankets, horizontal for swimming, etc... which let necklaces, bracelets, etc... off easier e) and my favorite: people taking off their jewelry for "safekeeping", before they go swimming, sports, etc... A LOT of jewelry gets lost this way, as people hide their jewelry in their shoes they've taken off, or other such "safe" places
Another place where its decent (yet not as good as swimming beaches), is sandboxes, particularly volley-ball courts. Perhaps there might still be a deal of aluminum trash in urban sandboxes, but you can't argue with the speed of target recovery in sand, which is very fast (when compared with trying to dig holes in turf).