Electron optics and microanalysis
GTK has a long tradition of microanalysis and electron optics with the first microanalyzer acquired in 1965 and the latest Cameca SX100 installed in late 2003. Most analyses produced in the lab are for the study of natural resource materials and in ore exploration.
The services provided at the GTK electron optical laboratories
Low vacuum SEM-ED
A scanning electron microscope (SEM) with possibility to detect and record:
- Secondary electron image - topography information from sub micron surface layers (mineral powders, coatings etc.)
- Back scattered electron image - mean molecular weight differences
- The SEM has a low vacuum option to study uncoated samples (gems, museum, archaeological, environmental samples etc.)
- Qualitative and quantitative analyses. X-ray distribution maps and phase maps.
- Rare phase locating from up to six separate samples during automated overnight operation. Locates all grains of interest (Au, PGE, U, Th) from polished sections or thin sections. Grains down to micrometer scale are found.
- Cathodoluminescence imaging.
- Qualitative analysis in a few seconds and a full quantitative analysis in 2-3 minutes.
- Quantitative analysis of elements from Be to U.
- Chemical composition determined at micrometer scale directly from a polished surface for solid materials. Point, profile and grid analysis. Quantitative analysis methods from full quantitative to cost effective fast analysis. Tailor made analysis methods according to the customers needs, i.e. diamond indicator analysis, concrete analysis, trace-element analysis.
- Element distribution mapping by beam or stage scanning. Mosaic images from whole thin sections. Quantified element distribution maps.
- Detection limit in routine analyses 0.01% and in trace element analysis even below 10 ppm.
- Non destructive method - the analysed material can be studied later by polarizing microscope.
Bo Johanson, tel. +358 29 503 2321 ja +358 40574 7439, e-mail: bo.johansongtk.fi
Marja Lehtonen, tel. +358 29 503 2183, +358 40 838 6999, e-mail: marja.lehtonengtk.fi