Fe-Co #

[maddogusmc]

Does anyone else ever get decaying zinc pennies ringing up Fe-Co numbers of 11-44, 12-44, 11-45, or 12-45? It seems to do it more if I have the sensitivity turned up high.

Mike

 

[detectorfreak74]

yes I did for a while and I found out the leaching in wet ground it gets worse ( you will get more depth in wet ground than dry but the leaching gives off odd signals the remedy to that is to turn down the variability down to about low 20s and that will help )

 

[maddogusmc]

yes I did for a while and I found out the leaching in wet ground it gets worse ( you will get more depth in wet ground than dry but the leaching gives off odd signals the remedy to that is to turn down the variability down to about low 20s and that will help )

Thanks, I'll try turning down the variability.

 

[detectorfreak74]

that should work for you and it gets rid of the high tones on the iron false

 

[Rolladex]

I find them all of the time. We call them a lawnmower penny's because the look like they been hit by one, and have the high numbers too.

 

[Goes4ever]

I can honestly say I have never dug a zinc that has ever registered higher that CO of 38

 

[maddogusmc]

I can honestly say I have never dug a zinc that has ever registered higher that CO of 38

What level do you run your variability?

 

[Goes4ever]

I run mine at 29

 

[Jack Flynn]

I can honestly say I have never dug a zinc that has ever registered higher that CO of 38

I'll second that and same variability. Have dug a few at 35 and 36.

 

[maddogusmc]

I run mine at 29

I also run mine at 29, maybe it has something to do with the soil, I live in Missouri.

 

[Goes4ever]

it could be, I set mine on 29 the day I got it, and have never changed it since, been almost a year and i have NEVER dug a zinc at numbers like you said......I wonder why you are getting that, that would be very frustrating.

 

[Bell-Two]

I have dug COPPER memorials at that number but honestly can't ever remember a zinc at that number.

 

[coolhandluke]

It is my understanding that variability dictates the degree of pitch from one tone to another. With a variability of 30 you get the biggest distinction between tone levels. I don't see how this affects the FE or CO numbers.

 

[maddogusmc]

I can honestly say I have never dug a zinc that has ever registered higher that CO of 38

I'll have to admit my ignorance of coins. I was looking at a minelab post on Fe-Co numbers for coins, and I didn't realize that copper pennies were made up to 1981. All the pennies that were giving me those Fe-Co readings fall into that time period. I just assumed that the zinc started in 1965, sorry, for my ignorance of the subject. Next time, I'll do a little research before posting something.

Mike

 

[coolhandluke]

They made the switch to zinc sometime in 1982. Some 1982 pennies are still primarily copper and some primarily zinc. By 1983 all new pennies were made using zinc.

1981 and younger = copper
1982 = copper or the new zinc
1983 and later = zinc

An easy way to tell a copper penny from a zinc penny without even looking at the date is to bounce it flat on a hard surface like a counter top.

The copper penny will "ring" and the zinc penny will make a dull "thud"

If it is a valuable penny you might not want to do that. But if you are just sorting the copper crap from the zinc crap it doesn't really matter.

 

[taltexan]

Memorial pennies run all over the scale....for me anyway...I hunted today and dug memorials from Cond.# 34 to 45 with FE # 09 to 13. It is really hard to tell what you got until you dig it up. Now Wheat's almost always hit 41 to 44 on the Co. I don't know if it is the machine or ground that is causing these numbers on Memorials. I have run sens. both auto and manual with no difference in numbers. I run variability at 28. Don't know really what else to do to get a smaller range for memorials. The rest of coins range as they should. As Goes says it is really aggravating with such a spread on these pennies.