Actually, I use three different "modes" to help identify those annoying nails and bits of iron. I set up in Ferrous Coin - Combined. I have one Pattern wide open and the other with a modified Coin pattern I built, based on US coins. It isn't anything special....I just scanned several hundred old coins under the coil, to make sure I wasn't missing anything I might find around here. (everything from nickels to silver 3-cent pieces to IH cents to silver dollars) I know some folks post that they've found coins with high ferrous numbers. But honestly, I can't remember digging any US coin with an FE reading more than 14. But, just in case I do come across one, or am unable to get a "clear" ID, my discrimination goes down to 16. Anyway, if I am in a park or yard, I'll hunt in the discrimination Pattern. If I am at an old farm site, I hunt in the open screen. I've pretty well explained my reasons in earlier threads. Regardless, if I get a hit that sounds good, I go back and forth across that target from a multitude of directions. Then I go back over the target using the other Pattern. By passing over the target in both Patterns, I am looking for consistency in sound, TID and location. If the audio breaks up from certain directions, I check the TID. A broken audio and fluctuating TID indicates a "non-coin" object. Typically, one with a high ferrous content. If that is the case in this target, I move on. However, if the sound is consistent, and the TID remains in the "keeper" zone, I check the target location. By location, I mean the exact spot where I could push a probe straight down and hit the coin. Then, after mentally marking that location with a leaf, clod or something in the grass, I go back over it in Pinpoint with Target Trace. What I have found is, when a deeply buried (rusty) nail is bent, it can sound like a coin from one or more directions in either Pattern. But when I go over it in PP, the location of a deeply buried nail will not be consistent with what I saw in the hunt Patterns. And, the "shape" of the target will not be symmetrical. By going over it in Pinpoint, and comparing the "location" with what I saw in Patterns 1 and 2, I can make a determination as to whether or not I want to dig it up. If they match up, I dig. If they don't, I keep walking.
Something interesting that I witnessed dozens and dozens of times before I started confirming location was, those darned nails were always "below and left" of where I thought the target should be. The easiest way for me to explain that is to compare the target location under the coil to the face of a clock. After Xing over the target, I was digging in the center of the coil, fully expecting to recover a coin. But over and over and over again, I would end up with a rusty bent nail at the edge of the hole in (what would be) the 7:30 or 8:00 position (if it were the clock face). Regardless of whether I initially found the target in Pattern one, and confirmed in Pattern 2, or vice-versa, I was still digging some nails. But when I started comparing the location of "exact target placement" by using both Patterns AND Pinpoint, my daily "collection" of bent, rusty nails has almost disappeared. Don't get me wrong. I still dig a few. But those few nails that I dig now are done so more to confirm what I expect, as to when I dug them expecting a coin.
Just something that works for me.
more for mineralized ground?