Sponsored by QATMReviewed by Emily MageeFeb 12 2025
In the world of geological and mineral analysis, preparing thin sections is critical for examining the internal structure and composition of rock samples. Using QATM equipment, we can ensure precision and reliability throughout the preparation process
Cutting and Grinding in Thins Section Analysis
The initial step of preparing the Thin Section involves cutting the rock sample to a standard size, fitting to a 48 x 26 glass slide, commonly known as the Giessner format. This precise cutting is typically done using the QCut 200A. The cut surface then undergoes grinding with P1200 grit silicon carbide paper to achieve a smooth finish.
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Gluing the Sample
Once the sample is adequately ground, it is glued on a glass slide, which has one side pre-matted for better adhesion. The epoxy mounting material is the preferred choice for this process due to its reliable bonding properties. The epoxy needs to be cured for 8 to 24 hours, allowing enough time for the adhesive to set thoroughly.
Further Cutting and Grinding
After the curing process, the sample, now securely attached to the glass slide, is subjected to further cutting and grinding. The QCut 200A, equipped with a diamond cup grinding disc, is used to grind the sample down to a desired thickness of 25-30 microns. This precise grinding ensures the sample is thin enough for microscopic analysis while maintaining structural integrity.
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Microscopic Analysis
The thin section is then covered with a cover slip and analyzed using transmitted light microscopy. This technique allows for a detailed examination of the sample's internal structure, providing valuable insights into its composition and characteristics.
Bulk Samples
For bulk sample preparation, the rock sample could be cut in a milling system as Retsch to a manageable size and mounted in epoxy resin. The mounted sample is then ground and polished using the Qpol 300A1 grinding and polishing machine. This multi-step process involves several stages of grinding and polishing to achieve a highly reflective surface.
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SEM Analysis
The polished bulk sample is ready for analysis in a scanning electron microscope (SEM). This analysis helps in determining the mineral and metal composition of the sample, which is crucial for mining companies seeking to optimize their refining processes.
Additional Methods
Different mounting methods are employed for non-homogeneous samples, including cold mounting, hot mounting, and UV mounting. Milling the sample to a fine grain size is also a common practice to get an even distribution of the sample.
Key Tools
- QCut 200A: Precision cutting and grinding machine.
- Qpol 300A1: Grinding and polishing machine for bulk samples.
- QATM Glass Slides: Tolerated closely around 1.6 mm thickness with a pre-matted side for easy adhesion.
Thin Section at a glance
- Cut rock samples to 48 x 26 mm Giessner format.
- Grind cut surface to P1200 grit with silicon carbide paper.
- Glue sample to 1.6 mm thick glass slide with epoxy.
- Cure epoxy for 8-24 hours.
- Use QCut 200A for further cutting and grinding to 25-30 microns.
- Cover thin section with cover slip for transmitted light microscopy.
This information has been sourced, reviewed and adapted from materials provided by QATM.
For more information on this source, please visit QATM.