Slightly masked nickels

I intended to answer this before.... but had no more time. (Using F-75).
+++ Let's say that you detect a slightly masked silver dime. Normally (without being masked) it would VDI at '71'. But now..... it's slightly masked. It may now VDI at '89'..... a somewhat "up-averaging" VDI common resultant. In both cases, the detector reports "hi-tone". No problems yet.

A slightly corroded buffalo nickel will VDI at '28' in open air...and audibly report as a 'hi-tone'. Now....... with this same nickel in the dirt ... in a natural setting and partially masked..... IT TOO will "up-average" (just like the silver dime) ,,,, to, say = VDI '47'. Hmmmmmm, now the nickel 'looks' like a soda tab to the detector...and the unit will now report the slightly masked nickel as a mid-tone. ((( All of this holds true for medium conductivity items...such as relics & gold jewelry ))).

ALL detectors have a difficult time ID'ing nickels. CZ's do the best ID job, but are not immune to EASILY mis-ID'ing nickels.

Closing point; ....If you are recovering Mercury dimes at (say) the 11" depth strata...... You may want to ALSO recover the 11" depth strata mid-tones.... as many of these will be the corresponding era Buffalo nickels.

Tom

I had this happen to me in a way. I put a silver dime on the ground and one at 7". The one on the ground ID at 71, the one 7" was on 88. So I call Fisher and one of the tech said to send it back and I did. They called me back 3 weeks later and said it was nothing wrong with the f75. I may be wrong but I think that the f75 is not as good on silver coin as the cz's, not saying that will not get them, but so far I have not got the silver coin as I was with the cz's. Will see how it works out. Thanks

Yes, mineralization and/or partial Fe masking will cause this. See how the unit works out on real hunts.