Well I didn't expect to dig this today, but glad it happened! Don't ever see or hear of early Mexican silver dug in a south Georgia plowed field! Bonus, arrowhead found nearby also!
MineLab E-Trac, MineLab Safari, MineLab Explorer XS,
White's 5000 D, White's 6DB, White's 5000 D GEB
Sunray X-1 for the ML's, Garrett PP for the White's and a Backhoe
Nice finds altogether, of course the 4 R's is special. A lot fewer 4 R 's were made than 8 R's. I looked it up in my old Krause catalog and there are two varieties listed for 1842 Zs 4 R's. A large letter and small letter types are listed, with the small letter variety being fairly scarce with an old value of $150 in just fine condition given. I'm not going to try to grade your coin, but is a nice example. I don't know which variety you have, but is in a nice state of preservation. Thanks for sharing !