? whats the word on gold prospecting with whites vision ?

[jimjim]

has anyone tried out the prospecting mode of the vision for small gold. does it find blacksand deposits. ect....

[Eu_citzen]

GMT is a dedicated gold detector.. Consider it, to.

As for the V3, look up on the White's Forum.
http://forum.treasurenet.com/whites/index.php

You might find it somewhere there.

[Steve Herschbach]

Hi,

I could find nuggets with a V3. Would I buy it for that? No. You are paying a lot for bells and whistles that have nothing to do with prospecting.

But if you have one and want to prospect with it, it is a capable detector. The 22 kHz mode is pretty hot. As far as black sand deposits go, despite all the talk about the subject I've never known anyone to really make much use of normal hand held detectors for that purpose. They can only find near surface black sand deposits and so would only work well in rare circumstances, like shallow dry wash deposits.

Steve Herschbach

[nuggetshooter323]

The only detector that I know that can do that is the GMT, even that is just a running numerical readout on the display. Your kind of going against the the tuning of your trying to detector, the whole point is to tune out the black sand.

[Jim Hemmingway]

The F-75 (and F-75 LTD) also has the Fe3O4 readout in the form of a calibrated bar graph. It presents this data independently of the ground phase measurement (ground balance) feature. A result is that you can “tune-out” the black sand with the ground balance adjustment, while still able to continue measuring its magnetic strength utilizing the Fe3O4 meter.

The Fe3O4 bar graph results (conveniently expressed as % volume magnetite) represent a measurement of magnetic susceptibility that results from any iron mineralization present in the soil. There are many non-conductive iron mineral types that contribute in varying degrees to a soils magnetic susceptibility. In similar quantity (amounts), many iron mineral types display very modest/slight magnetic susceptibilities compared to magnetite, regardless of their ground phase (ground balance) measurements.

Magnetite followed by another non-conductive iron oxide… "maghemite" …have the most profound impact on the Fe3O4 readout, as both materials are highly magnetic susceptible (of the two substances, magnetite is the more highly magnetic). Despite this strong similarity, these two substances demonstrate quite different ground phase measurements. On the F-75 scale, magnetite predominates from about 75 on up to maximum of 99, whereas maghemite tends to occupy a range that spans the low/mid 40s up to about 60ish.

Where both exist together (as is the case in many soils) the ground phase measurement falls between the respective ranges (subject to whichever substance is predominate) either substance tends to normally occupy. In this example, the soil’s magnetic susceptibility will be much more highly elevated than other soils that fall into a similar ground phase measurement range, but by comparison…contain less magnetic susceptible iron minerals.

An example supporting the above statement is the hydrated iron oxide “goethite”, prevalent in brown soils and northerly latitudes. While able to generate a similar range of ground phase readings to goethite...the magnetite/maghemite mixture used in this example will raise the magnetic susceptibility many times more than a similar amount of goethite or other weakly magnetic iron minerals.

Increased levels on the Fe3O4 graph readout indicate more highly magnetic susceptible ground, and thus more difficult ground to achieve good performance results with VLF units… by contrast to overall performance in relatively lower magnetic susceptible soils.

On the other hand, ground phase is a ground "target ID" measurement based on phase shift similar to any other (phase shift) target ID measurement that can then be further used for discrimination purposes. But in this instance, instead we adjust the ground balance accordingly, or perhaps with a slight positive ground balance offset to enhance fringe target signals...if that is your preference in any given location.

In summary, the Fe3O4 readout is a very convenient tool to identify the strength of soil magnetism, resulting in it's utility for locating shallow black sand deposits…as noted in an earlier post.

I realize the above varies a bit with the simple explanations provided in the manuals. The manuals do not sufficiently address the subject in my view.

Jim.