I used sodium polytungstate several years ago.  The material I used
was viscous, and required the use of a centrifuge to get separations
in anything other than geological time.

>Has anyone used LST (lithium-sodium heteropolytungstate) heavy liquids?
>We're considering this compound for separating aragonite (SG 2.93) from
>clays (2.9), and are concerned that, at pH 4, it'll dissolve fine
>carbonates (although the company, at www.heavyliquids.com, says it
>doesn't react quickly with limestone).
>
>Any info about this or alternate non-wickedly-hazardous heavy liquids for
>the purpose would be appreciated.
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Steve Nelson
Dept. of Geology
S389 ESC
Brigham Young University
Provo. Utah  84602

voice:    1-801-422-8688
lab:      1-801-422-5124
FAX:      1-801-422-0267

CARPE CARP:  seize the fish
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