How do you make a petrographic thin section?
The general preparation sequence for making transparent thin sections is as follows: sectioning, vacuum impregnation, grinding, cementing to a slide, resectioning, grinding and polishing. The preparation of thin sections is considerably more difficult than preparing polished bulk specimens.
Which instrument is used for thin section?
A geological cutting machine (GEOCUT) is used for thin sectioning rocks, glasses, ceramics, minerals, concrete, etc. It has a cast aluminum base, which houses the motor and the working space.
What is petrographic thin section?
In optical mineralogy and petrography, a thin section (or petrographic thin section) is a thin slice of a rock or mineral sample, prepared in a laboratory, for use with a polarizing petrographic microscope, electron microscope and electron microprobe.
How does a thin section work?
A thin sliver of rock or other sample material is cut using a diamond saw. This small piece of material is then ground until it’s optically flat using progressively finer abrasive grit. This means that light actually passes through the sliver of material. The standard thickness for a thin section is 30 microns.
What is a petrographic microscope used for?
A petrographic microscope is a type of optical microscope used in petrology and optical mineralogy to identify rocks and minerals in thin sections.
What is petrographic analysis?
Petrographic Analysis (ASTM C856) – A microstructural examination by optical and scanning electron microscopy (SEM) of the paste and aggregate on a prepared sample of concrete to look for features such as degree of cement hydration, microcracking, reaction products, breakdown of aggregate and evidence of poor freeze- …
What is the difference between a thin section and a polished section?
We have prepared standard thin sections of single grains smaller than 1 mm, and polished probe mounts of single grains embedded in epoxy as small as 125µm.
How thin are thin sections?
A thin-section is a slice of rock 30 microns thick. A single micron is 1/1000 of a milimetre.
What is ultrathin microtome?
Ultramicrotomy is mainly used as a sample preparation method for transmission electron microscopy ( TEM ). It permits the internal fine structures of samples to be visualized and analyzed at nanometer scale resolution. It produces ultrathin sections of samples in a fast and clean manner.