My advice for you when hunting the beach is to take it out of factory preset, turn on Iron Mask, and run it down to IM -16. This way you won't be missing a lot of signals that would equate to small thin gold bands...the kind that have big diamonds in them...and other things, like gold chains and earrings and stuff. Trying to discriminate trash at the beach is a sure ticket to finding mostly pocket change, silver rings, and maybe medium to large gold bands. As you can see from bob's numbers, trash and gold are too close to call. Best bet on the beach is to dig it all. I found a BUNCH of diamond rings this summer.
Here are some more numbers for you.
Fer/Con
One Dollar, Silver Eagle 00--15
One Dollar, Morgan 00--25,26
One Dollar, Eisenhower, clad 00--26,27
1/2 Dollars, walking Lib 00--28
1/2 Dollars, Franklin 00--28
1/2 Dollars, Kennedy, clad 00--28
1/2 Dollars, Capped Bust 00-29
Quarter standing Lib 00--29
Quarter, Wash, Silver 00--29
Quarter, Wash, Clad 00--29
Quarter, Statehood 00--29
One Dollar, Susan B. 00--29
One Dollar, Sacagawea 00--29
Quarter seated Lib 01--29
Draped Bust 02--29
Barber Dime 02--29
Seated Liberty Dime 03--29
Mercury Dime 03--29
Roosevelt Silver Dime 03--29
Wheatie 04--28,29
Gold 20 Dollars 04--29
Screw Caps 06/07 27/28
Memorial 06--27
Gold 10 Dollars 07--07
Gold 5 Dollar 07--22
3 cent silver 07--24
1/2 dime 07--24
Indian Head 07--25
Gold one dollar 08--04
Pull tabs 08/09 08/10
Gold 2.5 Dollar 08--10
Flying Eagle 08--11
18 kt 08-11 02-09
Indian Head, Fatty 08--12
5 cent, Silver war nickle 09--07
Beaver Tails 10--4
5 cent shield 10--05
5 cent, Liberty V 10--05,06
5 cent, Indian Head, Fatty 10--05,06
5 cent, Jefferson 10--06
14 kt 10-12 00-06
3 cent nickle 11--02
Foil 11--02
mens large ring 11--12
Wheatie, steal 31--28