The geochemistry and mineralogy laboratories specialise in the identification and analysis of rocks, minerals, soils and the fluids trapped in rocks. This information is used to support Geoscience Australia's national and regional programs, mineral systems research and regolith studies.
These laboratories use analytical techniques which are acknowledged as among the most powerful, most sensitive and most cost effective available. Expertise and facilities available for the preparation and analysis of geochemical samples include the following.
The swing-jaw crusher is used to reduce samples from 100 mm diameter to less than 20 mm diameter. The jaw faces are made of low contaminant mild steel.
The Boyd crusher with attached rotary sample divider reduces samples from less than 50 mm to less than 4 mm grains. The sample divider can be set to sample between 2% and 50% of the fine crush.
This unit is equipped with tungsten carbide blades and is used to clean weathered samples and to split large samples to fit the swing-jaw crusher.
This unit is used to produce a very fine powder from the coarse product from the Boyd crusher. Three grinding mediums are available:
Rocklabs swing-jaw crusher
© Geoscience Australia.
Boyd crusher
© Geoscience Australia.
Rocklabs hydraulic splitter
© Geoscience Australia.
Rocklabs vibratory ringmill
© Geoscience Australia.
The Philips PW 2404 XRF spectrometer with automated sample loader and online data processing is used for analysing fusions and pressed powder samples for elements with an atomic mass greater than 9. The equipment can measure concentrations as low as 1ppm and as high as 100%. A semi-automatic Initiative Scientific Products Fusilux 4X4 Fusion Machine is used in the production of fused discs and an Activon Automated Speca press for producing powder pellets.
The Leco C/H/moisture analyser is used for the determination of organic and inorganic carbon as well as bound water in rock and soil samples. This instrument not only determines total carbon and hydrogen but also the amount of the two elements given off and the temperature at which the two elements are given off.
Supplementary analyses such as moisture, ferrous iron, fluoride, loss on ignition and specific gravity also are available. Other specialised techniques may be used upon request.
The Agilent Technologies 7500 ICP-MS with automated sample loader and online data processing is used in conjunction with the X-ray Fluorescence (XRF) spectrometer for the analysis of a wide range of trace elements. Detection limits down to ppb levels can be obtained routinely. The ICP-MS is traditionally used with solutions, made by acid digestion of fused glass disks. The ICP-MS is also equipped with a Newwave UP-193 solid state laser ablation system for analysis of solid samples.
X-ray fluorescence spectrometer
© Geoscience Australia.
Leco RC-412 multiphase
carbon/hydrogen/moisture analyser
© Geoscience Australia.
Liz Webber doing ferrous iron analysis
© Geoscience Australia.
Inductively coupled Plasma -
Mass Spectrometer (ICP-MS)
© Geoscience Australia.
The HORIBA Jobin Yvon SuperLabram laser Raman microprobe has a fully confocal microscope and is used for the rapid and non-destructive analysis of solids, liquids and gases. The high spatial resolution of this instrument (≥ 1 micron) makes it particularly suitable for the identification of gases and solids in fluid inclusions. The laser Raman microprobe is also equipped with a motorised stage, which allows Raman mapping of selected areas of the sample. An optical-fibre probe can be attached to the spectrometer and used for probing larger samples that do not fit under the microscope, such as hand specimens and drill core.
The Seimens D500 X-ray diffractometer (XRD) is used to identify and determine the amount of minerals in powdered samples. The Siroquant software package is used to quantitatively determine the amount of each mineral identified by its X-ray diffraction pattern.
The Integrated Spectronics PIMA is a field-portable, shortwave infrared spectrometer which provides rapid data on rocks and minerals. The accompanying software contains a library of PIMA mineral spectra allowing easy interpretation of unknown spectra. Measurements can be made on all types of samples including diamond drill-core, RC and RAB chips, powders and soil samples.
The Cameca SX-100 electron probe micro-analyser is a shared Geoscience Australia-Australian National University facility used for the analysis of elements in very small areas such as individual mineral grains. It is equipped with four wavelength dispersive X-ray spectrometers and an energy dispersive spectrometer. Cathodoluminescence and backscattered electron images also may be obtained in the scanning mode. This instrument is primarily used for major element microanalysis with detection limits typically exceeding 50-100 ppm. However, detection limits may be extended into the trace element range by the use of longer counting times and precise background corrections.
These laboratories contain the following heating and freezing stages which are used mainly for fluid and melt inclusion studies.
These laboratories contain a range of research-grade, polarising microscopes and binocular microscope including:
X-ray diffraction spectrometer
© Geoscience Australia.
Anthony Budd using stereo
binocular microscope
© Geoscience Australia.
Laser raman microprobe (LRMP)
© Geoscience Australia.
OZCHEM is a database of whole-rock and stream-sediment geochemistry samples which are mainly from Australia, Antarctica, Papua New Guinea and the Solomon Islands. Both major and trace element analyses are included. Analyses are added from:
Terry Mernagh +61 2 6249 9640