Congrats on that nice Merc!! For me, it's the most common silver coin that I find and I never get tired of digging one up. That 1828 property should have all kinds of coins and other cool stuff. If possible, don't be afraid to re-hunt the whole property. I'm currently re-hunting two properties from the 1800's and am somewhat embarrassed about the coins I missed the first time. Good luck!!
My options are limited, so I return there often. Unfortunately on my Vanquish, nails hit between 18-25, and, sometimes, it's hard to distinguish between a nail and a coin. I've found pennies that read from 18-21 that sounded like a nail so now, I dig em all. The way I figure it is, I'll eventually clean up all the nails, and, possibly, find things that were being masked by them. I have two churches that I hunt, one built 1828, the other 1873. I had another property that dates back to the 1700's but I lost that permission, twice now! The guy's daughter-in-law asked him to stop me because I was "finding all the treasure!" She had just gotten a detector. I showed the owner what I normally find, and said, "fine, let her have a go at it, and she'll see that it's not that easy to find things. The guy drives trucks which are parked on site, has farm equipment, and the whole propert is junky as hell, with tons of shredded aluminum, cans, bullets,etc. Came back a year later and he let me go again, then stopped allowing anyone on his property after he and his wife were nearly shot but a hunter he'd allowed on his land; the guy is in his 80's. I will try again in the fall, but don't know if he'll let me back. It's a shame though, because I've found early 1800's flat buttons and a Continental Army General Service button on his property. Also, there is an old well on the property lined with huge stones, and covered with a large milling blade. I don't grid places out, I just kind of wander around, get a bit of excericse, and hope to find some nice items. Around here, most people, for some reason, don't want you on there property. Just got turned down to hunt a spot up the street that has an early 1800's
Summer Kitchen on the property. The lady said people had detected there before and found nothing. I said, "Technology has gotten better over the years, would you mind if I gave it a try?", she immediately said no. She really gave no explanation. Oh well, all I can do is keep trying.