Hi - I need a liquid which has either a higher specific density then
rock - 2.7 to 3.0 g/cm3 and is completly enviromentally FRIENDLY - I
already checked most salt solution but the once that I could find are
all toxic -- OR -- a workable device that moves clear water in a way
that it would have the same effect - I was thinking of moving water
upwards in a pipe so the friction of the water against a rock would
keep it floating where as a heavier object would sink down.

sodium polytungstate

Isn't this what drilling fluid ("mud") does in oil well drilling:
http://www.baroid.com/esg/sd1384.jsp

As lewismelville has already commented,  sodium polytungstate (SPT) is
now routinely used as a heavy liquid for separating different minerals
according to their density (instead of the toxic/carcinogenic
halogenated organic compounds we used to use when I was in grad
school!). For example, see <http://www.sometu.com/index.html>.
Different densities can be achieved simply by varying the
concentration of this water-soluble compound in a solution.  As the
density increases, though, so does the viscosity of the solution.  If
lower viscosities are required, then lithum polytungstate can be used
instead.  <http://www.heavyliquids.com/product_LST/lst.htm>

elemental gallium has a density of 5.9 g/cm3 and is 
considered to be relatively safe in the environment. 
it does however solidify below 25C (77F), so it may
or may not "float your rock".  Also, you mention
'clear water' and suggest that you are looking for a 
clear liquid...