Why are we still in the dark ages

I thought the cheapest detectors (i.e. the one I have) detected all metals? Hence when we look for a "iron rod" we typical find everything - beer cans, coins, chocolate bar foil wrappers, mobile phones (dug up three so far), the lining inside cigarette packets ...

I have set lightweight aluminum conduit or pipe and stainless steel over rebar set in wetlands for an object that would not rust away and would hold the steel remains inside for a Schonstedth to find later.

0.02

Most metal detectors that are not magnetic locators respond to the product of the metal's conductivity and the surface area presented to the detector coil, and inversely with the distance. There are some variations in treasure hunter designs that alter that but only a little, and some have smarts to do a better job of recognizing changes from the soil to a metal object.?ÿ Those generally rely on steady movement of the coil to recognize a sharp change.?ÿ

A pop top may show up as strong as a vertical aluminum pipe if only the end is presented to the coil.

The conductivity of common metals in decreasing order is silver, copper, gold, aluminum, ..., brass, zinc, ..., iron.?ÿ

So with iron so far down the list, you definitely want the magnetic locator for it if the object has any length to it.

If you are looking for a bronze or aluminum cap, a treasure hunter type is quite useful. I wouldn't go hunting one without my detector.

@bill93

So, "pin-finders" of the Schonstedt type, are actually magnetic field detectors?

Posted by: @richard-imrie

So, "pin-finders" of the Schonstedt type, are actually magnetic field detectors?

Yes.?ÿ They work on the principle of a magnetometer.?ÿ The Schoenstedt has two sensors spaced 15 or 18 inches apart in the pipe and it reads the difference in magnetic field for those two locations.?ÿ Take a screwdriver or nail and run it up the pipe to see where.

Iron will "suck in" the earth's magnetic field (soft iron effect) and/or have its own permanent field, so the difference grows stronger when nearer the iron.

?ÿ

I can imagine a shonstedt, with a piggy back aluminum, gold, silver detector. Ya never know... Ya might find a pot-o-gold, and retire, if you had more than an iron detector!