cans...

[grasshopper]

are cans made of the same stuff that some siver coins are?? i always get readings of 75 and higher and sometimes they turn out just being a can.
is there any way to tell a difference??

[cjoej]

It's not unusual for an aluminum can (at say 6") to show up as a coin (at 2"). To the detector it registers with about the same strength signal and that causes it to be displayed as a coin.

SWC
Joe

[bigjohn]

but ya got to dig em. my u.s. buckle read real big knew it wasnt a coin but was glad i dug it.

[bigbillinsc]

they are the purest form of aluminum. even foil used in cooking and packing is an alloy. cans arent. being as conductive as they are is why they read shallow when they are buried deep. My whites prizm 3 maxxes out on coins between 7 and 9 inches in my soil here.... i have dug a six pack of cans (crushed flat and aranged in a six pack at tiime of burial) at 13 inches after breif shower. it is the return electrical signal thaht your machine is looking at and compareing to the signal it sent out. by discriminating out aluminum you could also cheat yourself out of some gold. gold alloys 10kt and 14 kt are made up of all kinds of alloys. notch out the aluminum and you will notch out some gold 2.

[cjoej]

That’s true about having to dig to find out for sure, and I don't pass them up myself. With Silver, copper and aluminum being the best conductors of electricity they also respond best to our detectors, so discriminating aluminum is useless if you want to find coins. There has been some technology to identify target size (Garrett), but even this could cause you to pass up an exceptional find, so just dig it and hope for something good and if it is a can, recycle it.

While we are somewhat on topic; the claim that detectors can "see through" an iron pot or can to pick up coins or gold is ABSOLUTELY NOT TRUE. What the detector will "see" is only the outside of the item, (I once saw this proven with 24K gold plated sterling silver medallions weighing 2.1 Oz., they read more like trash because all the detector saw was the gold plating which gave a poor response).

The "halo" created by corrosion of the item and its contents may be able to carry some of the internal coins oxidation to the outside of the container for the detector to "see". Now this will not contain gold because gold does not corrode (that is why it is used in electronics, esp. electric contacts). However most gold has an alloy such as copper or silver to harden it and give better wear, so the alloy can corrode and enhance the signal. It is because of the variety & amount of alloys that we get such a wide variety of signal responses for rings, jewelry and gold coins, even two seemingly identical rings of the same Karat can give different returns due to different alloy material. Position of the item and size will affect the return signal as well as soil conditions.

Well so much for an impromptu lesson...hope it helps you understand a little more of what's going on below the surface.

SWC
Joe

[grasshopper]

that makes a lot of sense. thanks everyone.

[pris]

Wow, Joe! Great lesson. I already knew about the halo effect, but your explaination was great. I really appreciate that people on this forum are so willing to help others and give advice. There is so much knowledge available and at our disposal in this forum. It's amazing. Amazing, I tell you!