Mineral Exploration Network (Finland) Ltd. has developed and implemented in prospecting an original geo-chemical survey based on
MEFFA – Multi-Element Fine Fraction Analysis
Efficiency of early stage mineral exploration depends on the number of analyzed
geochemical samples. As the size of exploration targets is getting smaller sampling on
more detailed grid is required. The number of samples collected could be up to 10000
samples per month for one exploration target. During base metal exploration, portable
XRF analyzers prove to be the most effective method of generating quick and accurate
analysis, but do not detect gold and many other elements at the levels required in
A solution could be the development of an effective
geochemical survey method based on simple and productive sampling technique and
analytical methodology with acceptable detection limits for elements, that cannot be
detected by portable/mobile XRF analyzers, and with high production rates. Sample
preparation should be simple and should exclude chemical dissolution of samples. Using
analytical complexes should be reliable, easy to set up and maintain and affordable for
junior exploration companies.
Initial development and test work of MEFFA has been done by Mineral Exploration
Network (Finland) Ltd., at the company’s analytical laboratory using an analytical
complex based on Laser Ablation (New Wave 226) and ICP MS (Agilent 7700). The
method includes original techniques of field sampling and sample preparation without
dissolution or leaching of the sample material, measurement, results processing,
interpretation and mapping.
The initial investment in the project was done by MEN Finland Ltd. during 2012-2014, is
€450 000. In 2013 in Finland and in March of 2014 in Spain, the company received the
first positive results of MEFFA analysis (please see the Presentation attached).
Benefits and Strength of MEFFA:
– High productivity –
– Field sampling – averaging 300 samples a day taken by one field pair;
– Sample Preparation – about 200 samples in an 8 hour shift by two lab technicians;
– Measuring – up to 400 samples/day in an 8 hour shift by one lab technician;
– Low cost of sample preparation and analysis;
– Does not need specialist facilities for sample preparation, first stage – fine fraction separation could be done in field environment. It reduces samples to 3-5 gram so sample transportation and logistics are getting much easier.
– Environmentally-friendly as there are no acids used in sample preparation.
For more information please download presentation in English: MEFFA_presentation
and in Russian: MEFFA_MINEX_2017