Sieben

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Probenaufbereitung2.png Probenaufbereitung > Probenaufbereitung: Methoden Methoden > Alle Methoden Alle Methoden > Sieben


Sieben


RetschAS200.JPG

1- Sieve your sample using several sieves. Use the following table to help decide on the combination of sieves you want to use.


Mesh # mm
9 2.0
16 1.0
32 0. 5
60 0.25
100 0.15
200 0.075
325 0.0475


2- Select the appropriate sieved fraction depending on the grain size of the mineral you want to separate. Generally you should use the sieve size that is ~ ½ the grain size of interest. Note that the fraction below 200 mesh tends to be useless for separation of all minerals except your clay fraction. For most purposes (age dating, stable isotope work), you will find the fraction between 32 and 60 mesh most useful, especially for further processing with the Frantz.

3- Examine the different size fractions optically (using a binocular scope if needed) to determine which size fraction contains the highest concentration of the mineral you wish to separate. Note whether that fraction needs further disaggregation or not.

4- Once your separation is complete, you have to clean the sieves. The sieves are cleaned with compressed air, a toothbrush (for the fine sieves with large mesh #’s), or any other sturdy brush.