[size=large]ATTENTION DEVOTED COIN HUNTERS[/size]
I’m fortunate, in many ways, to live here in the USA. I have enjoyed Coin Hunting since I got my start in the hobby in March of ’65 and have been fortunate to chase all sorts of coins, even our modern-day “clad” coins, but they have all been made up of non-ferrous, good-conductivity metals. All of us here in the USA still have metal money made of better quality metal alloys and, because of that, we can use our detectors and enjoy more consistent audio responses, and more reliable visual responses, too. The Target ID is usually a tighter and more consistent numeric VDI.
For those who live in countries that have chosen to use less quality and less conductive metals, especially metal, or metal alloy mixes, that are ferrous/magnetic based metals, you have my deepest sympathy. Ferrous metals have a different effect on an EMF [size=small](electromagnetic field)[/size] than non-ferrous metals. Ferrous or magnetic metals would be Nickel, Iron, Steel and other similar substances. Non-ferrous would be Brass, Copper, Gold, Silver, Zinc, and such.
Hunting any site that contains ‘iron’ targets, such as nails, rusty tin, washers and other kind of common items, can create a number of annoying, variable responses. A straight iron nail can be reasonably easy to reject. A nail that is bent in a 90° angle or other odd shape can be more difficult to reject and sometimes produce a better response, even if only on occasional coil sweeps.
Why do they do that? Because man took a low-conductive, poor quality ferrous object and re-shaped it. The result is that while easy to reject in one shape or form, the new shape enhanced its conductivity and that makes it more of a challenge for a detectorists to learn to deal with. Can we think of other annoying targets that man shaped out of a magnetic/ferrous metal? Of course, they are the crimp-edged “crown caps” also called “bottle caps.” What we have to do is learn how to ‘classify’ such targets so that they will identify their true character and produce a more negative response with an ‘Iron’ audio and/or ‘Iron’ visual Target ID reference.
For over three decades I have used a simple example to demonstrate how ‘MAN’ can alter a piece of terrible ferrous junk so that it produces a more desirable, higher-conductive and better response. To understand how difficult it is to find metal coins made of challenging non-ferrous material, although you might have seen me post this elsewhere, you can do this.:
A..
1.. Get a metal paperclip, just a common paperclip, and since most are made of a non-ferrous metal, make sure it is attracted to a magnet.
2.. Straighten out the paperclip so-as to look like a piece of wire.
3.. Lay it flat on the ground and adjust your metal detector’s Discriminate mode to the lowest setting possible and sweep over the straight paperclip.
4.. Sweep the search coil over this target from each direction and adjust the Discrimination to the LOWEST setting that just barely rejects this sample target. Just barely.
B..
1.. Re-shape the metal paperclip so that it forms a ‘U’ shape. .
2.. Lay it flat on the ground and sweep over the re-shaped into a ‘U’ paperclip and listen for any difference in response. Also observe any visual display response.
3.. If you get a response from the ‘U’ shaped paperclip from the previous Discrimination setting for ‘A’ above, then GENTLY increase the Discrimination only enough to just barely reject the same, but shape-altered paperclip.
C..
1.. Re-shape the metal paperclip so that the two ends are slightly curved, and form the ferrous paperclip into an 'O’ shape. Connect the two hooked ends to make good contact.
2.. Lay it flat on the ground and sweep over the re-shaped into a 'O’ paperclip and listen for any difference in response, also checking the visual response.
3.. If you get a response from the connected ‘O’ shaped paperclip from the previous Discrimination setting for ‘A’ and ‘B’ above, then note the audio response and the visual Target ID response. Is this what you would expect from a nasty-bad iron piece of junk? Does it create problems with rejection and/or Target ID?
It is the same piece of metal, no difference in metal make-up or length or weight, but it is now more of a challenge and sounds kind-of-like a desired target you might want to recover, yet at the same time it has similar responsive properties of those blasted, crimp-edge ‘Bottle Caps’. If you have some problems identifying or classifying ferrous or magnetic targets like rusty washers and crimp-edge bottle caps it is because man has shaped them into a more-conductive round shape that enhances their conductivity, just as man [size=small](You)[/size] did with the reshaped paperclip.
Well, that’s a problem similar to what many people in many countries outside of the USA have when trying to Coin Hunt for their ‘goofy metal’ coinage. Since you’re in Canada and sent me some of your modern coins, here is what I faced in trying to evaluate low-grade, ferrous/magnetic metals that Canada has used for their more modern-year coins.:
Value Years Composition of Canadian Coins
I’ll use blue to identify the primarily good quality metal coins, Ag = Silver, Al= Aluminum, Au = Gold, Cu = Copper, Sn = Tin, Zn = Zinc
and red for those that are made primarily of a magnetic or ferrous-type metal such as ‘steel,’ Ni = Nickel, .
1¢
1908-20 95.5% Cu, 3.0% Sn, 1.5% Zn
1920-41 95.5% Cu, 3.0% Sn, 1.5% Zn
1942-77 98.0% Cu, 0.5% Sn, 1.5% Zn
1980-81 98.0% Cu, 1.75% Sn, 0.25% Zn
1982-96 98.0% Cu, 1.75% Sn, 0.25% Zn
1997-99 98.4% Zn, 1.6% Cu plating
2000- 94.0% steel, 4.5% Cu, 1.5% Ni, (*) (NOTE: Magnetic!)
(*) Note that some pennies in 2000-01 had copper-plated steel compositions,
as evidenced by a small “P” under the Queen.
5¢
1908-19 17.5% Cu, 92.5% Ag
1920-21 20% Cu, 80% Ag
1922-42 99% Ni
1942-43 88% Cu, 12% Zn
1944-45 chrome plated steel
1946-51 99.9% Ni
1951-54 chrome plated steel
1955-81 99.9% Ni
1982-99 75% Cu, 25% Ni
2000- 94.5% steel, 3.5% Cu, 2% Ni plating
10¢
1908-10 7.5% Cu, 92.5% Ag
1910-19 7.5% Cu, 92.5% Ag
1920-67 80.0% Ag; 20.0% Cu
1968-77 99.9% Ni
1978-99 99% Ni
2000- 92% steel, 5.5% Cu, 2.5% Ni plating
25¢
1908-10 7.5% Cu, 92.5% Ag
1910-19 7.5% Cu, 92.5% Ag
1920-67 80.0% Ag; 20.0% Cu
1967-68 50.0% Ag; 50.0% Cu
1968-99 99.9% Ni
2000- 94% steel, 3.8% Cu, 2.2% Ni plating
$1
1987- 91.5% Ni electroplated with 8.5% bronze plating
$2
1996- outer ring = 99% Ni .. Inner core = 92% Cu, 2% Ni, 6% Al
Okay, now that you can see which coins are made with a ferrous or magnetic type metal that, in their rounder shape, have enhanced conductivity, you will learn how these will sometimes give a higher-reading Target ID, as did the paperclip formed into a connected ‘O’ shape. In evaluating these coins I could get some higher Target ID read-outs with both the Makro Racer and Nokta FORS Coin & Relic that challenged me when I swept over them with the center-axis of the search coil.
The visual Target ID numbers varied from a somewhat tighter reading to a more widely-spread range of inconsistent numbers similar to encountering a Bottle Cap or similar favorably-shaped but poor quality metal target. I then backed the search coil off to about ½-the-distance between the center of the search coil and the front or rear ‘tip’ of the search coil’s overlapped DD internal windings and noted a response. Most often it was degraded and much jumpier and lower-reading.
Finally, I backed the search coil up a little more so that I was at the outer-edge or just maybe about 1” to 1½” beyond the front ‘tip’ or ‘edge’ of the search coil, as if using my EPR [size=small](Edge-Pass Rejection)[/size] Technique to check a target like a Bottle Cap or rusty washer where I ‘classify’ those targets as being probably bad and ferrous-based when I am searching an old picnic grove where I frequently encounter bottle caps.
I use the EPR Technique in those and similar environments so that I can class the encountered target as likely a ferrous bottle cap and ignore it to move on and find coins. It’s worked well for me for decades because I live in the USA and don’t have to deal with poor-quality metal coins.
If I were to visit Canada and search an old picnic grove that was popular in the 1920’s to maybe the early 1960’s, and used my 'EPR' techniques to ‘classify’ pesky Bottle Caps, I would still get favorable responses with a tighter, more consistent Target ID response from most of the better-quality, higher-conductive Canadian coins and would miss only a few types.
However, if I searched a more modern-use Canadian picnic grove I would come across many coins that would irritate me with poor-TID, bottle cap type read-outs, such as:
1¢ Pennies made from 2000 to present.
5¢ Nickels made from 1922 to 1942; 1944 to 1981; and 2000 to present
10¢ Dimes made from 1968 to present.
25¢ Quarters made from 1968 to present.
$1 and $2 coins include ALL of them. The $1 “Loonies” are almost all Nickel metal composition with a bronze plating, but the $2 “Toonies” have an outer ring of the same bad quality Nickel, but an inner core of 92% Copper giving them a little different challenge in conductivity.
I used the small DD coils on both the Nokta FORS CoRe and Makro Racer; the 5½X10 DD on the Racer; the ‘standard’ 7X11 DD coils on both the FORS CoRe and Racer. Note that any change in search coils can make some differences in the Target ID, as can a radical change in ground content. In all cases the coins were laid on top of the ground that was free of any nearby metal.
I Ground Balanced over the same spot and, depending on the search coil mounted or detector in-hand, the Ground Phase read-out varied from 80.[size=small]80[/size] to 82.[size=small]00[/size] with three different detector models and 8 different search coils. With the Racer, depending upon the search coil used, the MMI [size=small](Magnetic Mineral Indicator)[/size] showed between ‘5’ and ‘7’ segments filled at the spot where I Ground Balanced. So, I used this morning’s ‘bad ground’ conditions and added them to those I did before over ground that balanced at 77.[size=small]20[/size] with only ‘2’ to ‘3’ MMI segments activated, as well as some indoor “in air” testing.
A C = the Centered coil response, and EPR is for the just at or out-from-the-edge response from the front of the coil to classify a target as a possible ferrous or non-ferrous target.
Using the Canadian Coins Sven sent me, and averaging the TID read-outs as explained, here are the results I had.:
1¢
1982 C= ± 84 … EPR = favorable response
1998 C = ±82 … EPR = favorable response
2011 C = Very inconsistent with some higher TID numbers at times from 67 to 83 … EPR = Junky, iron-range jumpy audio and visual response.
5¢
1975 C = 83 to 90 … EPR = Junky, iron-range jumpy audio and visual response.
1997 C = 54 to 58 … EPR = Junky, iron-range jumpy audio and visual response.
2003 C = Very inconsistent with some higher TID numbers at times in the 50’s … EPR = Junky, iron-range jumpy audio and visual response.
2013 C = Very inconsistent with some higher TID numbers at times in the 50’s … EPR = Junky, iron-range jumpy audio and visual response.
10¢
1983 C = 81 to 86 and still jumpy … EPR = Junky, iron-range jumpy audio and visual response.
2001 C = Very inconsistent with some higher TID numbers at times in the 40’s to 80’s, but mostly a junky, iron-range jumpy audio and visual response.
2014 C = Very inconsistent with some higher TID numbers at times in the 40’s to 80’s, but mostly a junky, iron-range jumpy audio and visual response.
25¢
1985 C = 85 to 88 … EPR = Junky, iron-range jumpy audio and visual response
2005 C = Very inconsistent with some higher TID numbers at times in the 80’s, but mostly a junky, iron-range jumpy audio and visual response.
2012 C = Very inconsistent with some higher TID numbers at times in the 80’s, but mostly a junky, iron-range jumpy audio and visual response.
$1 aka “Loonie”
2008 C = 83 to 87 … EPR = but mostly a junky, iron-range jumpy audio and visual response.
2012 C = 83 to 87 … EPR = but mostly a junky, iron-range jumpy audio and visual response.
$2 aka “Toonie”
1996 C = 82 to 86 just inconsistent. … EPR = Junky, iron-range jumpy audio and visual response.
2012 C = 82 to 86 just inconsistent. … EPR = Junky, iron-range jumpy audio and visual response.
Yes, this is another one of those ”Monte Responses” and that means it is lengthy. Sorry about that. I thank ‘TallTom’ for his contribution below, and I am glad he indicated the dates of the coins he sampled. There is a lot to learn when you evaluate any of your own country’s coinage as well as that from foreign places, and Canada is far from the only one that makes use of Nickel, Steel and other ferrous-types of metals.
You will note that some coins appear to be made of similar materials but gave somewhat different responses. That’s just how it goes because it depends upon the purity of the metal used, the source of the metal used, and in cases of mixed metals and/or plating, you can have more differences in the quality and thickness [size=small](or wear)[/size] of the plating process used.
Just for added amusement I laid these 17 coins on the ground in one area, Ground Balances, and used both the Di2 and 2-Tone modes as well as Di3 and 3-Tone modes, then increased the Discrimination to an ID Mask/ID Filter setting of ‘40’, as if I just didn’t want to find much iron trash at all. I approached each of the coins and made sure I swept the center axis of the coils directly over the coins. With that high Discrimination setting I either got no target signal response at all, or a very terrible and only spotty ‘blip’ and not a ‘dig me’ response at all from 2001 1¢; the 2003 and 2013 5¢ coins; none of the 10¢ coins, and not the 2005 25¢ coin.
I have lived in NW Oregon for almost 54+ of 66 years come June and used to find a lot of Canadian coins. Fortunately, the bulk of them were from the “better years” when their mintage was of a high-conductive quality material. In recent years I have found few of the Canadian coins, and I know I have easily by-passed some when they were in trashier sites, such as parks and picnic areas, because they behaved so similar to bottle caps and other low-grade ferrous-based material.
To conclude:
I can only suggest to all Canadians that they do the following:
1.. Continue to seek older-use locations and search for the better quality coinage, such as silver 10¢ and 25¢ coins from 1920 to 1967; copper based 1¢ coins from 1908 through 1996; and 5¢ coins with silver from 1908 to 1921, and mainly copper from 1942-43 and ’82 to ’99. In short, go find the ‘good stuff!’
2.. Search with a lower Discrimination setting so as not to reject too many newer types of Canadian coins made of magnetic and ferrous metals, like nickel and steel.
3.. Ignore any visual Target ID reference because junk-metal coins will respond like junk-metal bottle caps and junk-metal washers, etc. Search mainly by listening for a good or iffy audio response, then recover the targets. That means you take a ‘Beep-DIG!’ Approach for successful hunting and recover a lot more trash to find many more modern coins.
4.. If you live in the USA or any other country that has relied on non-ferrous metal to make your coins, be very pleased and enjoy your detecting time as you’ll have less frustrations from ferrous-metal coins that response like many trash targets, enhanced because ‘Man’ happened to shape them such that they have more conductivity to cause some good-sounding responses.
Monte
