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- Sediment (~10 grams)
- Add small amounts of HCl (10 or 30%) at a time until the reaction with carbonate is over. Fill up with water.
- Centrifuge (2500 rpm, 5-10 min) and decant.
- On the vortex make sediment loose and add small quantity of HF (38-40%) and let react. Add more HF until reaction is over (in total about 50-70 ml HF) and put on shaker for 2 hours (not heated).
- Add water until bottle is filled and centrifuge (this step I have never done, so I guess also 5-10 min at 2500 rpm?) and decant
- Make sediment loose again from bottom of the bottle on vortex (if it is under the fume hood otherwise do not).
- Add HCl to disaggregate silica gel up to less than half bottle
- Fill up the bottle with water
The Q Question here if we want to centrifuge again or we go upstairs to the paleo lab with this bottle (still containing some acid).
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