Karen, you might try going into your dept. mineral collection and get a 
ksp and plag crystal large enough to cut/grind into cubes several mm on 
a side.  Then I would keep them in a plastic bottle [500 ml?] with 
tetrabromoethane or bromoform.  Acetone/heavy liquid can be added in 
small quantities until one cube sinks and the other floats.  Quick and 
easy.



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Steve Nelson
Dept. of Geology
673 WIDB
Brigham Young University
Provo, UT  80602

801-378-8688 voice
801-378-8143 FAX

"Intel Inside" is a warning label
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