Low VDI on a penny?

[Hart-IN]

Anyone ever have a copper cent hit hard and steady at a VDI of only 20?

 

[BarnacleBill]

Air test? Or in the ground? Or in the ground and then once recovered still reads ID 20? Is it a clad steel coin?

HH
BarnacleBill

 

[Hart-IN]

Thanks for the reply, BarnacleBill.

I almost passed on it in the ground. I thought it would be a pulltab but turned out to be a badly worn 1858 Flying Eagle cent. It also air tested a solid 20 on the X-terra and read as a pulltab on my ACE 250.

 

[BarnacleBill]

I believe the Flying Eagle is composed of 88% copper and 12% nickel which will bring the ID down the scale compared to a pure copper cent. Also being very worn can drop a segment along with any chemical changes to the surface.

HH
BarnacleBill

 

[Digger]

As I listed in my X-Terra TID chart, IH cents can read anywhere from 24 -32. And those numbers are just from several hundred IH cents I've found over the years. I've never found a Flying Eagle. Nor do I have all IH dates. So the TID of 20 really doesn't surprise me. I appreciate your posting on here so the rest of us know what we might be passing up by not digging those consistent "20" targets. Any chance you'd post a picture of it so we can see the condition?

Thanks again. And congrats on finding a coin that has eluded me for these past 36 years! Flying Eagles are on my list of things to do before I'm gone! HH Randy

 

[Hart-IN]

Thanks BarnacleBill and Digger. I will try to get a better picture but there really is almost no detail left. With a 10x magnifier I can only make out "858" in the date, The basic outlines of the eagle on the front and the wreath on the back side.

I found this on my second hunt with the 70 and I am fairly new to detecting (started in September) but I thought that since it is thicker and heavier than IH's and memorial cents that it would actually have a higher VDI, like maybe 38-40. I had to find out if anyone else has ever had one read this low because of the chart in the FAQFAQ. In your chart you said you had some IH's as low as 24 but they were usually a little higher, is that a correct assumption? I would have passed on this coin in the ground if it wasn't such a solid repeater on the VDI and the tone wasn't choppy at all like pulltabs usually are.

Thanks guys for helping me learn this machine. I really appreciate you taking the time to answer my question.

Scot

 

[Digger]

I based the TID chart I made solely on coins I have dug. I ran several hundred IH cents under the 9-inch concentric at 7.5 kHz for the chart. Bench test. No dirt! I found the lower readings always matched up to coins in the 1860's and 1870's. Those newer than the late 1870's read provide higher TID numbers. I kind of figured the metallic content must have changed about the late 1870's, explaining the different readings. But when I investigated small cent metallic compositions, I find that Flying Eagles, 1859 Variety 1 Indians and Variety 2 Indians (up into mid-year 1864) were made of 88% copper and 12% nickel. Starting in mid-year 1864, Variety 3 was introduced and is referred to as the Bronze cents due to their 95% copper and 5% tin and zinc content. Based on that, it becomes obvious that those minted with 95% copperand 5% tin and zinc will read higher than those of 88% copper and 12% nickel. But tying the TID to dates (other than metallic differences) is no more the answer than it was when I tested all those silver dimes. Seems that individual coins, even when minted the same year, will vary. About the only explanation I can come up with is the current condition of the coin.

Hey, I have a great idea........ if everyone here would send me a Proof set of each year of every coin, I'll make another TID chart!

Until then, I guess I'll just keep digging those consistent signals, regardless of the numbers. JMHO HH Randy

 

[Hart-IN]

As your tag line says. "You'll never know for sure......unless you dig it! Thanks again for the help.