signal from 2 rocks from Garrett AT gold, no response from Pinpointer?

[texasvarmit]

I was metal detecting with a Garrett AT gold at our place in Coal Cty. Oklahoma Saturday, an old property once used a little for farming, and mostly hunting. Found a lot of spent bullets etc but found 2 rocks, that gave me a good signal with Garrett AT gold, but when using the Garrett Pinpointer the rocks do not set it off.

Don't ask me which of the three modes I was in when found these as I was experimenting with various modes and iron disc so don't recall the mode when found. What is odd to me is the pinpointer does not give signal on these rocks, but the big detector does. They are lightweight, i.e. 10 grams for small one and 20 grams for large one.

Could they just be mineralized rocks, or what? I know they are not meteorites, nor do they appear to be iron rust concretions, etc.

any thoughts welcome. I have detected in north Texas and Virginia and never run into this type of thing before.

 

Amazon Forum Fav 👍

Minelab PRO-FIND 35 Waterproof Pinpointer Metal Detector for Experts with Tone ID & Adjustable Sensitivity - Grab it through Amazon!

[turtlefoot13]

Where I live in the Ozarks, natural hematite would set off one of the detectors that I had. I could not disc. it out. None of my other detectors would pick it up, even in all metal mode. Your rocks don't look like the hematite that I used to find though. My guess is something similar. Can you try an experiment and see where the AT Gold picks it up and where it will disc. it out?

Doug

 

[texasvarmit]

turtlefoot,
Yeah I will try that and post results. I forgot to mention the rocks have no attraction to a magnet either.

 

[texasvarmit]

in Disc 1 mode, the detector gives the iron signal clear up to a setting of 44 on iron discrim. though you have to have it close to the coil, it also gives a signal as iron when iron discrim is turned down to almost around 3 or so, then goes to non iron signal.

 

[turtlefoot13]

I am guessing that it is hematite (or similar "iron" based mineral). Some of the hematite that I have found is magnetic and others is not. Have you done the needle test? Take a light sewing needle and let it hang from a piece of thread and move the needle close to the rocks. You will be surprised at how many rocks a magnet will not stick to, but will attract a "free hanging" needle.

Doug

 

[texasvarmit]

I am guessing that it is hematite (or similar "iron" based mineral). Some of the hematite that I have found is magnetic and others is not. Have you done the needle test? Take a light sewing needle and let it hang from a piece of thread and move the needle close to the rocks. You will be surprised at how many rocks a magnet will not stick to, but will attract a "free hanging" needle.

Doug

wow, now there is an idea I had not thought of and would not have thought of! I left both my quality magnetic compasses at the cabin (a 3 hour drive one way) but will do that next time I am up there, or get a compass I can trust here.
thanks for the excellent pointers!!