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1.

Place ~2 cm3 of undried sample into a centrifuge tube with 25 mL of acetic acid (10% solution).

2.

Mix well, and let sit until the reaction ceases (using the agitator in the chem lab helps).

3.

Shake well again to ensure the reaction has stopped (i.e., no more bubbles).

4.

Spin sample in the centrifuge (15 min at 1500 rpm)

5.

Decant the acetic acid solution and dispose of the acid solution properly.

6.

Add 25 mL of DI to the centrifuge tube and centrifuge again for 15 min at 1500 rpm.

7.

Decant the clear water.

8.

Repeat the "wash cycle" (Steps 5 and 6) with DI.

9.

Place washed sample in a large beaker with some distilled water and a little 1% Calgon.

10.

Suspend the clay material by placing the beaker in a sonic dismembrator for ~1 min.
Note: Do not let the sample heat up.

11.

Transfer the sample to a clean centrifuge tube and spin for 5 min at 1000 rpm to remove the >2 µm size fraction from suspension

12.

Remove the <2 µm size fraction by collecting the top 1 cm of solution with an eye dropper.
Note: If it is necessary to re-suspend flocculated clay particles using the dismembrator add more Calgon solution. 15 min at 1500 rpm in the centrifuge may not settle the <2 µm particle size. Increase the speed to as much as 5000 rpm to remove the clay from the Calgon solution.

13.

Make an oriented clay mount by placing 2–3 drops (enough to cover the quartz disk) of clay suspension onto a glass slide and let dry in a desiccator.

Wash at least 3X

1.

Add 25 ml of 1% Borax solution to the clay plug 

2.

Dismembrated sample (machine is auto set on time), to remove the >2 um clay fraction

3.

Centrifuge for 4 mins at 750 rpm, decant the suspended liquid into a separate centrifuge tube (you should end up with a ~full centrifuge tube of suspended clay)

4.

Repeat steps 1-3 on the remaining >2 um fraction

5.

Centrifuge the <2 um fraction for 15 mins at 1500 rpm to remove the Borax solution 

6.

Decanted and add 25 ml of nanno pure water

Centrifuged for 60 mins at 3000 rpm, the liquid decanted before loading onto a zero background silica disk

1.

In centrifuge tube, mix a small amount of bulk sample (~5 mL) (fresh, not dried) with 1% Calgon solution. Use an ultrasonic bath or dismembrator, if necessary.

2.

Centrifuge the Calgon solution/sample mix at 1000 rpm for 5 min to remove the >2 µm particle-size fraction.

3.

Decant the Calgon solution (containing suspended clays) into a new centrifuge tube, and spin it at 1500 rpm for 15 min to remove the remaining <2 µm clay-size fraction.

4.

Decant the Calgon solution and wash the clay residue with distilled water.

5.

6.