Geochemistry Division


The Geological Survey offers a broad-spectrum assistance to the people of Namibia and undertakes many collaboration projects with research institutions, local or abroad, with the aim to advance the geoscientific knowledge of our country to the benefit of the people of Namibia.
Division Geochemistry & Laboratory The tasks of this division is two-fold, namely the assay of samples received from geologists, institutions and the general public and the collection and assay of soil samples within the Regional Geochemical Sampling Program.
Subdivision: Analytical Geochemistry The laboratory section contains a wide range of modern facilities, and can conduct high-quality mineralogical and inorganic chemical analyses of minerals and rocks, as well as industrial mineral quality tests. This is accomplished with some of the most sophisticated analytical and preparative instruments in the southern hemisphere:
A Wave-length dispersive X-Ray Fluorescent Spectrometer (XRF, Philips PW2404 with ProTrace)) for the analysis of major, minor and trace elements, 36 elements from F – U in the periodic table, including some light elements considered very difficult to analyze. This is supported by an automatic fusion machine and a semi-automatic pelletizing press for the preparation of fusion discs and powder briquettes of the samples for analysis.	`
An additional improvement has been the acquisition of an automatic dosing machine (dossier) which is used for weighing the Loss On Ignition (LOI) in the preparative stage of the sample for XRF measurement.
In addition, an Inductively Coupled Plasma - Atomic Emission Spectrometer (ICP-AES, Varian Liberty 110) is available to complement the XRF application with respect to sensitivity and/or sample medium, like water samples. A Teflon bomb system and a Microwave lab-station (Milestone MCR 6E) is available for sample digestion to extract the elements into the liquid phase for measurement with the ICP.

For the identification of minerals an X-Ray Diffraction instrument (XRD, Bruker AXS, D8 advance) is available. The D8 advance computer bank contains a vast number of reference scans for the accurate mineral identification
A new automatic Thin and Polished Section Preparation system (Logitech, LP50) is now commissioned to prepare the valuable and essential thin sections for all geological work.
Apart from the analytical instruments, sophisticated optical polarizing microscopes are available suitable for transmitted and reflected light, coupled to a computer for imaging and recording.
For additional work and sample preparation facilities are on hand to do the following: Cutting and polishing of rock specimens of various sizes Splitting, crushing and pulverizing of rock samples Sample size analysis Sieving of unconsolidated material into fractions with an automatic sieving machine Mineral separation by heavy liquid media separation, magnetic separation and Wilfley table.
Subdivision: Regional Geochemistry The Regional Geochemical Sampling program, started in the year 2000, is a project which will eventually supply much valuable information with respect to potential mining sites, land use planning, environmental monitoring and pollution control. The work program of the project entails the sample collection, their analyses and entry of the results into the database of the Earth Data Namibia. These will be made available to researchers, potential investors and the general public.

It is approached a sheet at a time, and the choice of sheet is determined by the following factors: Does additional information exist, like high-resolution airborne geophysics? Does it contains mineralization with economic potential? Is the area of socio-economic-ecologic interest?
It is envisaged that the programme eventually covers the whole of Namibia. The programme involves collection of stream sediments or soil samples over a wide area with a moderate sampling density of 1 sample per 10 km2. Sampling points are determined prior to sampling and dependant on the topography of the area. The map alongside depicts the progress of the program to date. Click on the map to view a larger version.
Additional information about each sample site has to be given including the lithology of the surrounding bedrock and of any mineralization found. Great care is taken that each sample is representative of the spot taken and free of contamination through human or animal intervention.
With the large number of samples collected and expected, systematic sorting, recording and archiving of the samples has to be ensured.
In addition to the above facilities and activities, the laboratory complex also houses two specialist laboratories, one for engineering geological tests (including instrumentation to test compression, shear and drill rock core) and the other for the testing of Industrial Minerals (with instrumentation like a hydro-cyclone test rig, thermo-gravimeter and X-ray sedigraph) These labs are more application oriented to assist with hands-on solutions in use-related projects or concerns on the ground.