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1. Place sample in centrifuge tube with 25 ml mL of 10 % Acetic Acid for at least 1 hour to decarbonate (it helps to place the centrifuge tubes on the agitator in the cold room) 
2. Centrifuge for 15 mins at 1500 rpm, decant and wash with 25 ml of nanno pure mL of nanopure water (3X to remove all Acetic Acid)

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1. Add ~25 mL of a 1 % borax solution into the centrifuge tube. Borax prevents the sample from flocculating. Too much Borax however will increase flocculation. 
2. Put the tube into the bottom clamp inside the dismembrator case. When satisfied with the positioning, press the "Start" button on the probe power supply (Figure 17B). If the material does not appear to be circulating throughout the whole tube or the tube is heating up, adjust the probe position and start the dismembration over.
3. Let samples settle overnight (~12 hours). The next morning, the material should be separated out with the clear liquid filling most of the tube and sediment filling the bottom cone.

"Quick and Dirty" Clay Separation Method: Not for Semi-quantitative Analysis

Standard IODP Clay Separation Method: Not for Semi-quantitative Analysis

1. In centrifuge tube, mix a small amount of bulk sample (~5 mL; fresh, not dried) with 1% borax solution. Use agitator or dismembrator, if necessary to suspend particles.
2. Centrifuge the borax solution/sample mix at 750 rpm for 4 minutes to remove the >2 µm size fraction
3. Decant the supernatant liquid (containing suspended clay) into a new centrifuge tube 
4. Centrifuge the <2 µm fraction for 15 mins at 1500 rpm to remove the Borax solution
5. Decant the borax solution and add 25 mL of nanopure water to wash the clay
6. Repeat Steps 4 and 5 as necessary to remove the borax (USGS recommends repeating up to 4-5 times)

Alternative method from Exp. 379

1. Add 25 mL Add 25 ml of 1% Borax solution to the clay plug 
2. Dismembrate the sample (machine is auto set on time), to remove the >2 µm clay fraction
3. Centrifuge for 4 mins at 750 rpm, decant the suspended supernatant 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 µm fraction
5. Centrifuge the <2 µm fraction for 15 mins at 1500 rpm to remove the Borax solution 
6. Decant and add 25 ml of nanno pure mL of nanopure water
7. Centrifuged for 60 mins at 3000 rpm, the liquid decanted before loading onto a zero background silica disk.

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1. Take the <2 µm clay fraction, this should be rinsed and free of any treatments, in centrifuge tube add ~20 ml mL of 1N HCl
2. Vortex the sample to completely dislodge all material before pouring sample into a 100 ml beakermL beaker, add stir bar once sample is in place
3. Set hotplate to 300°C (boiling point of HCl is ~101, but in order to maintain a continuous boil the hotplate needs to be much hotter)
4. Set the stir RPM below 100, this is only to keep the material suspended within the HCl
5. Start time once the samples have come to a complete boil, leave for 2 hours — add more HCl as necessary (DO NOT, let the sample go dry and burn)
6. Once the sample has boiled for 2 hours, turn off hot plate and allow sample to return to room temperature before pouring beaker contents back into a clean centrifuge tube, rinse beaker with DI water to collect all material
7. Centrifuge down for 15 mins at 1500 rpm, decant acid and rinse with 25 ml nannopure mL nanopure (3X)
8. After samples has been washed 3X and is free of HCl, centrifuge for 60 mins at 30 rpm

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