Instrumentation GDD Inc. 2018-09-18 Page 7
5 Important tips for getting good results
The SCIP (Sample Core Induced Polarization) measures geophysical properties of the ore such as
apparent resistivity and chargeability. The SCIP simulates an Induced Polarization survey. The
waveform is ON+, OFF, ON-, OFF. The current flows through the sample and is then switched off.
While the current is flowing through the sample, a resistivity (Rho) is calculated from the ON Time
Voltage. When the current is switched off, the voltage across the sample drops and a decay curve
is measured. The Chargeability (M) is calculated from this DECAY.
Here are a few tips about preparing and measuring your core samples:
Note: It is very important to always use the same methodology and keep the samples under
the same environmental conditions for all measurements of all samples in order to compare
them with each other.
Soak your core samples in water for a few days before testing them.
It is recommended to soak the samples in water in order to keep their properties as in
the natural environment. The best way to take measurements would be on fresh
samples. If it is not possible, two days of soaking should be sufficient. Note however
that it is not necessary to leave the samples to soak. The important point is to keep the
same measurement conditions for all samples. The values will not necessarily match
with field data but the measured values of a sample compared to another one allows
defining which ones are less resistive and/or more chargeable. You may then correlate
anomalies versus results from the field.
Note: The use of distilled water by osmosis could dilute the natural salts contained in
the samples and falsify the measurement results. In this case, the use of running
water seems an acceptable compromise.
Remove the excess of water on the core sample before beginning the measuring process.
Use a saturated copper sulphate solution.
To take a measurement, the sample is fixed between electrodes by using sponges
dipped in copper sulphate solution. Make sure that some copper sulphate crystals are
not dissolved in water to get a saturated solution.
Before starting the measurement, make sure that the core sample is completely dry on its
surface.
During the whole measuring process, make sure that the work bench, the core holders and
the rod that fix together the core holders are completely dry.
