Hi Matthew, Welcome to the wonderful world of clay mineralogy !
Separating the clay (typically <2 um) by gravity settling is actually preferable to centrifuging, as you can more easily check for flocculation. [If this is a problem add some drops of sodium hexametaphosphate (‘Calgon’) solution.] At BGS, we dry our isolated <2 um fractions right down in a moisture extraction oven (set at 55degC), homogenise and then resuspend a known amount (¬80 mg) to produce a consistently thick oriented mount. If you are not aware of it – Moore & Reynolds (1997) is the bible for clay preparation and analysis – very easy to follow. Moore, D.M. and Reynolds, R.C. 1997. X-Ray Diffraction and the Identification and Analysis of Clay Minerals, Second Edition. Oxford University Press, New York. Best regards, Simon Simon Kemp Senior Mineralogist p +44 (0)115 936 3448 e s...@bgs.ac.uk w www.bgs.ac.uk British Geological Survey | Nicker Hill | Keyworth | Nottingham NG12 5GG | UK [cid:image001.png@01D76E53.4D8B1360] Profile<http://www.bgs.ac.uk/staff/profiles/0778.html> | Twitter<https://twitter.com/SimonKempBGS> | Research Gate<https://www.researchgate.net/profile/Simon_Kemp2> | Google Scholar<https://scholar.google.co.uk/citations?user=UcipPfUAAAAJ&hl=en> From: rietveld_l-requ...@ill.fr <rietveld_l-requ...@ill.fr> On Behalf Of Matthew Rowles Sent: 01 July 2021 05:26 To: RIETVELD_L Distribution List <rietveld_l@ill.fr> Subject: Clay sample preparation Hi all I’m gingerly venturing into clay analysis. I’ve done previous analyses on pre-separated clay fractions by resuspending the clay in a little ethanol and dripping onto a Si wafter to make an oriented mount (which is then also successively glycolated and heat treated). I have some upcoming work which will necessitate creating the clay fraction. I don’t have a centrifuge, so I have to separate the clay fraction by settling. The USGS methodology looks like a good method to follow: https://pubs.usgs.gov/of/2001/of01-041/htmldocs/methods/decant.htm After I’ve suctioned off the clay suspension, what is the best way to get at the clay? Leave it settle more? Evaporate the water? (I’m also in the middle of commissioning a spray-drier, so that will help with the random mounts.) Thanks Matthew Rowles This email and any attachments are intended solely for the use of the named recipients. If you are not the intended recipient you must not use, disclose, copy or distribute this email or any of its attachments and should notify the sender immediately and delete this email from your system. UK Research and Innovation (UKRI) has taken every reasonable precaution to minimise risk of this email or any attachments containing viruses or malware but the recipient should carry out its own virus and malware checks before opening the attachments. UKRI does not accept any liability for any losses or damages which the recipient may sustain due to presence of any viruses. Opinions, conclusions or other information in this message and attachments that are not related directly to UKRI business are solely those of the author and do not represent the views of UKRI.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Please do NOT attach files to the whole list <alan.he...@neutronoptics.com> Send commands to <lists...@ill.fr> eg: HELP as the subject with no body text The Rietveld_L list archive is on http://www.mail-archive.com/rietveld_l@ill.fr/ ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
