Target id – Nokta detectors Fors Gold User Manual

Page 27

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Magnetic Mineralization level ranges from 0-99 and is

displayed in the Magnetic Mineralization Indicator on the

right side of the main screen. This measurement can be

summarized as the amount of the magnetic property and

intensity of the ground. Simply, if you are working on a

ground with intense and magnetic minerals, this value will

Tough ground conditions occur especially if the conductivity and magnetic properties of

the ground are intense. Most of the time, correct operation of the device on such ground

is possible with accurate mode selection, proper ground balance, sensitivity and threshold


Stones and rocks or dips and holes in the ground affect the quality of searching and target

detection as much as the ground itself does.

Soil and rocks have two different properties just like the targets you are searching for. One

of them is the intensity and the other one is the conductivity - magnetic permeability ratio

and these two properties are independent from each other. In this manual, the

conductivity - magnetic permeability ratio will be referred to as ID in short. High magnetic

permeability, low conductivity results in low ID. Soil or rocks can be highly permeable and

have low or high IDs as well. If the conductivity increases relatively to magnetic

permeability then the ID will also increase.

Hot rocks are classified as negative or positive based on their ID being low or high in

comparison to the ID of the soil they are in. One or both of the types may be present in a

field. The negative and positive effects mentioned here will only be valid if ground

balancing is properly done on the existing ground. Otherwise, soil itself will not act

differently from hot rocks in terms of ID. In ''Ground Tracking'' however, conditions will

differ. Therefore, the effects of hot rocks in ''Ground Tracking'' will be discussed separately.

Here we are referring to a proper ground balance without ''Ground Tracking''.

Positive hot rocks act and sound just like metals. In the General Search mode, when you

sweep the search coil over them, they tend to give a short ''zip zip'' sound. If the signal is

strong enough, the device may also give an ID for these rocks. Negative hot rocks, on the

other hand, tend to give a longer ''boing'' sound when the search coil is swept over them.

The device will not give an ID for these rocks regardless of the signal strength.



FORS / Page 26

be high. If the ground has low magnetic intensity, this value will be small.

This measurement is important from two aspects. First, detection depth is low in areas with

high magnetic mineralization and the user should be aware of this fact. Magnetic

mineralization is very high especially in ''black sand'' where ''magnetic iron oxides'' (these

are not iron, their effect is in the opposite direction) are abundant. As experienced gold

prospectors know, the possibility of finding gold in black sand is high. Therefore, very high

values of magnetic mineralization may indicate the presence of gold. Second, magnetic

mineralization is a property also found in hot rocks and measuring its level will play an

important role for the device to eliminate false signals caused by hot rocks.




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