FerroFluid that does not stain?!

[etay herz]

I've been experimenting with ferrofluid and reading alot about it but i couldnt find any where on the web info about ferro that does not stain glass or see- through plastic?

is there such a thing? i really hope there is, if there is can anyone tell me how to make it or where to buy it??

thanks.

[hermanntrude]

the stuff i made is messy for sure but it doesn't exactly stain glass, just leaves a thin layer which comes off with a good solvent. Mine was magnetite in parrafin (kerosene)

 

I did see somewhere a recipe for an aqueous ferrofluid, which may or may not be less of a staining problem:

 

LINK