"Joseph Gwinn" wrote in message
...
In article ,
Sunworshipper SW@GWNTUNDRA wrote:

On Wed, 2 Feb 2011 21:41:47 -0800, "Steve B"
wrote:


"Jon Anderson" wrote in message
...
On 2/1/2011 10:19 PM, Steve B wrote:

She built a viewer out of 4" PVC with a glass bottom, and walked the
creek.
In the first week, she found one nugget the size of a golfball, and
several
smaller ones of good weight. Hugh gave up on all the heavy stuff and
just
used the underwater viewer after that.

Another neat item, though a lot pricer, is the White's Goldmaster,
tuned
specifically for gold.

The 16 to 1 mine in Allegehaney, California, has taken to using metal
detectors quite a bit. They found one dang decent size specimen in a
well
traveled tunnel, just a foot or two inside the rock. They'd been
walking
right by it for many years and had no clue it was there.


Jon

IIRC, they are the prime method of finding gold in Australia, and
companies
have even made specific models to deal with Australian soils. I have
been
using mine for looking for meteorites. None yet, but some possible
specimens. I use three neodymium 1.5" disks right now, and boy, you can
hear it when something clicks and jumps on the magnets. Will have these
analyzed at some time, there is a lot of iron in the soils hereabout,
the
next county north being Iron county, and iron ore to make cast iron has
been
mined there for 150 years now.

Steve


You should see it up here by Iron Mountain Mi. My cheap metal
detector in Vegas would beep loudly over a penny, up here the penny
doesn't ever beep at all. Matter of fact, the thing has a tone and
goes blank over something metal and back to a tone here unless it's an
anvil.

Wonder if this has anything to do with it.

http://thebigfoto.com/earths-gravity

I seem to have moved to a big low spot. I'd like to make a
magnetometer some day. Plus try to get it to work just above or below
water.

Has nothing to do with gravity.

The issue in Australia and I assume Iron Mountain is that there is a lot
of various kinds of ferrite in the soil, which raises the background
level, making for instance that penny less visible to a detector.

Joe Gwinn

"Ground balancing" is a very important feature of any good metal detector,
and one that is not understood very well by many operators. Plus, the soil
conditions can change five feet from where you set it.