The thing is that a chain consists of small rings, each of them is below the device detection threshold. By this we mean a minimal target that can be detected by a metal detector. MDs see the chain not as one target, but as an array of separate rings. However, if the chain stays in the ground long enough to oxidize, a metal detector will be able to “see” it, since there’ll be established an electronic connection between the chain rings.
The same type of question is – whether a metal detector will identify some gold sand. Of course, it will, if there’s a small hill of it on the table or the sand is put into a box. However, if you scatter it over the table, the electromagnetic connection breaks and the MD won’t be able to detect separate sand grains regardless of their number.
Why doesn’t my metal detector see a chain? It is a high frequency one (with 100 kHz operation frequency).
Though Safari, E-Trac, CTX 3030 have operation frequency from 1.5 to 100kHz, their sensitivity is set low intentionally to detect such small targets and avoid digging out lots of small sized rubbish. Still, you are going to find some pellets, pieces of foil etc. These MD models have high operation frequency to perform discrimination better. From technical point of view, it is rather difficult to design a metal detector capable of identifying small rings of a chain and showing high detection depth. That’s why metal detector models are divided into beach hunting and treasure hunting ones.
Beach hunting MDs designed exactly for small targets searching (chains as well), for example Garrett АСЕ150, АСЕ250 or AT PRO models have not very sufficient detection depth, but they are highly sensitive to small targets.
However, consider the following idea – while you are complaining that your MD doesn’t see a chain, think, whether it is worth spending time on it? Any chain is usually light weighted (not more than 1-2 grams) and while you were digging out some trash looking for it, you could have found some massive rings with another metal detector.
However, there is a small trick you can use when searching for chains. If during metal detecting you find a golden pendant or a cross pendant, it is quite possible that its chain is somewhere around, since in most cases the pendant was lost when the chain got unsnapped or torn. That’s why when you find something like these, study the area more thoroughly and don’t skip any target sending a signal.
MD settings required to look for golden chains:
- Set the device sensitivity to its maximum value.
- Use concentric or mono coils of small diameter (9” or even 6” large).
- Set discrimination mask to search for jewelry.
- Using headphones is a must.