MNetrac -
There are some excellent tips up above - I love to read tips posted by others as I've picked up some very solid ones over the years that have helped me while I'm out detecting.
Personally, I have dug up a number of higher conductive, high ferrous signals (i.e. 26-45) and they turned up to be coins with iron. But it doesn't happen every time or even the majority of the time, I would say like 25% as a guestimate. Certain audio/visual signals make me suspicious a signal is only iron falses and similar signals make me suspicious they are good items with adjacent garbage, usually rusty iron.
Fortunately, the e-trac software is very good at giving you hints that the coil is seeing something down there besides rusty iron. Some additional tips I will add to those above:
1. Adjacent targets, especially surface targets, can mess up your ability to ID and pinpoint a target of interest. If they are somewhat easy to remove, do so. Make it easier on yourself. I am still surprised how many 'iffy' targets completely disappear when I get a surface pull tab, bottle cap or zinc penny removed and then go back to my 'target'.
2. As you circle around a target to pinpoint and get a good target ID on it, lift the coil as you ID the target and see how quickly you lose the signal. If you think you have a deep, whisper of a silver dime, and you lift the coil several inches and it is still there, it is more likely a small shallow target posing as something better.
3. How thoroughly you hunt an area is often determined by how much time you have and whether you anticipate coming back again. If you are hunting a one time shot place, estimate your time available vs. real iffy targets. If you aren't sure about spending the time digging a target, mark it with something you can easily see and move on to the rest of the area and then come back if you have time. If you have time, then go over it again and decide whether to give recovery a shot, and then make a mental note of how it turns out. You will start to see trends that will help you on future hunts.
4. Don't stop investigating a hole just because you find a rusty old nail; the Minelab BBS and FBS detectors excel at finding good targets in with the rusty iron. There may very well be a coin, token, relic or jewelry in that hole with the rusty nail.
5. Use a good quality pinpointer and make sure if you are pinpointing w/one capable of discrimination, like the SunRay X-1, that you are in quickmask with an open screen. You will be amazed at the number of large and small bits of rusty iron down there with your Barber Dime that has been hiding for the last 110 years. And finding multiple coins (pocket spill or coin spill) in the same hole does happen on a somewhat frequent basis.
There are lots of other tips that you will see posted. Keep a sharp eye out and don't be shy about asking questions. With the SLOW time (Winter) approaching all too quickly here in North America, use some of that down time to search back through previous posts and find those of interest. I'm sure they'll help when breaks come in the weather and we can get back out and hunt.
Rich (Utah)