Nontoxic, high transmittance, high density fluid

[MegaKuo]

Hi, I'm looking for a liquid that is nontoxic, high transmittance, has a specific gravity higher than 1.3.
Here is the catch. I'm using it to separate resin, so it can not dissolve or react with resin.
there was a similar topic on high density fluid on other forums, but I'm using it differently.
I'm no chemist.Really need some help.

 

[DrDu]

potassium formate brine
https://www.google.de/url?sa=t&rct=...ta.pdf&usg=AFQjCNGXuBY98fTuWfqfS3pCiQxwQcSgqg

 

[Ygggdrasil]

Glycerol has a density of 1.26. I don't know, however, if it will react with or dissolve resin. You could also try a water/sucrose solution: http://lclane.net/text/sucrose.html