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Chapter 4 MXT Display
Ground phase indications are a doubled edged
sword. Higher numbers simply mean predominately
ferrous (iron) such as black sands / magnetite.
Lower numbers simply mean less iron and/or
predominately conductive nonferrous (not of iron)
content, such as gold per ton of rock. So in a dry
wash, outcropping, or vein, a shift in either direc-
tion (higher or lower numbers) may be of interest.
For example a black sand streak may have a lot of
flour gold at one end. It will indicate a high ground
phase number on the end without the flour gold, and
a lower ground phase on the end with the flour
gold. The same applies to veins or an outcropping.
It is the change that brings about the interest more
so than if it is either high iron (high number) or
high conductive (lower numbers). Knowing that the
ground is high iron (magnetite), outlining black
sand pockets, and checking veins for consistency
(change), and comparing rock samples for possible
assay, are the common uses of ground phase.
Again, change is of the most interesting, not direc-
tion.
3. GND - Indicates the phase (measurement) of the
ground . This is useful in two different environ-
ments.
A. Within a dry wash the gold will settle
with the heavier materials (black sands).
When searching you notice the ground
phase is declining (lowering in number),
generally you are working further away
from the heavy black sand deposits. If you
notice the ground phase is increasing,
generally you are working toward (closer) to
the heavier deposits. By following the more
intense ground phase you increase your
likelihood of finding nuggets.
B. Checking outcropping or veins, the
ground phase can also be useful in a similar
way by indicating the consistency or change
of the veins ground phase.
Generally speaking, the ground numbers will hold
fairly consistent in most open terrain areas, such as
hydraulic sites and desert areas. GND readings in
the high 70's and 80's are considered heavy iron
mineralization. Alkali or salt areas will display
much lower numbers, possibly into the 30's and
40's.
Black sand streak-heavy iron mineralization
Alkalai or salt area in a dry wash
Flour gold
concentration
at one end of
black sand streak
NOTE: Watching the change in Ground Number in the upper right of the display, you will first look
for a change to a high number indicating high mineralization or black sand. When that streak is
identified you will then look for the Ground Number to lower again at one end of the streak indicat-
ing where the flour gold concentrated or washed down to that end.
Use Ground Numbers First to Find Gold Bearing Ground in a Dry Wash
