Inorganic Geochemistry Laboratory
Laboratory Manager: Liz Webber
Telephone: +61 2 6249 9088
- Equipment, Capabilities and Services
- Geochemical Analysis
- Mineralogical and fluid inclusion facilities
The Geochemistry and mineralogy laboratories specialise in the identification and analysis of rocks, minerals, soils and the fluids trapped in rocks. This information supports Geoscience Australia's national and regional programs, mineral systems research and regolith studies.
Expertise and facilities available for the preparation and analysis of geochemical samples include:
Rocklabs hydraulic splitter: 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.
Rocklabs swing-jaw crusher: 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.
Boyd crusher: The Boyd crusher with attached rotary sample divider reduces samples from less than 50 mm to less than 4 mm. The sample divider can be set to sample between 2% and 50% of the fine crush.
Rocklabs vibratory ringmill: This is used to grind the coarser product produced by the Boyd crusher to a very fine powder. Three grinding media are available include:
- Tungsten carbide (contaminants Tungsten and Cobalt);
- Chrome steel (contaminants Fe, Cr, Mn, C, Si, Ni and V); and
- Tool steel (contaminants Fe, Mn, C, Si).
- X-Ray fluorescence (XRF) spectrometry: 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 to produce fused discs; and an Activon Automated Speca press for producing powder pellets.
Laser ablation and solution inductively coupled plasma - mass spectrometry (ICP-MS): The Agilent Technologies 7500ce ICP-MS with automated sample loader and online data processing is used for the analysis of 45 trace elements. Detection limits down to ppb levels can be routinely obtained. The ICP-MS is traditionally used with solutions, made by acid digestion of fused glass discs. The ICP-MS is also equipped with a Newwave UP-193 solid state laser ablation system for analysis of solid samples.
Leco RC-412 multiphase carbon / hydrogen / moisture analyser: 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 measures the quantity of carbon and hydrogen present in the sample, the temperature at which they are liberated and the total carbon plus hydrogen.
Volumetric, gravimetric and electrochemical methods: Supplementary analyses such as moisture, ferrous iron, fluorine, loss on ignition and specific gravity also are available.
Other specialised techniques may be used on request.
- Laser Raman microprobe (LRMP): 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 equipped with a motorised stage also, 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.
- X-ray diffraction spectrometry: The Seimens D500 X-ray diffractometer (XRD) is used to identify 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.
- Portable infrared mineral analyser (PIMA): 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, reverse circulation (RC) and rotarty air blast (RAB) chips, powders and soil samples.
- Electron probe micro-analyser (EPMA): 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.
Heating and freezing stages: These laboratories contain the following heating and freezing stages which are used mainly for fluid and melt inclusion studies:
- Linkam MDS (IR-adapted) 600 stage (-196°C to +600°C). This stage is mounted on an infrared microscope equipped with a Hamamatsu IR camera and a mercury lamp for UV illumination. The Linksys software is used for automated temperature control and capture of digital images at specified time or temperature intervals.
- Linkam TS 1500 stage (20 to 1500°C). This stage is automatically controlled with a TS94 programmer.
- Fluidinc modified USGS gas flow stage (-196 to +700°C). This stage is mounted on a microscope equipped with a Sony video camera for viewing.
- ChaixMeca stage (-196 to +600°C).
- Leica 1350 stage (25 to 1350°C).
Transmitted and reflected light microscopes: These laboratories contain a range of research-grade, polarising microscopes and binocular microscope including:
- Leica DMRX polarising microscope which can be operated in transmitted or reflected or both simultaneously and is equipped with a Leica DFC 320 digital camera for microphotography;
- Leitz Orthoplan polarising microscope equipped with mercury lamp for UV illumination;
- Leitz Orthoplan polarising microscope equipped with a Leica DC100 digital camera and diamond-coated microdrill for cutting small sections from petrological thin sections;
- Olympus BX60 polarising microscope equipped with IR Optics and IR camera (400 - 2200 nm) and mercury lamp for UV illumination; and
- Wild M400 Photomakroskop - stereo binocular microscope.
Topic contact: firstname.lastname@example.org Last updated: December 16, 2010