loss tangent of materials

hi all!

is there any material that has more losses (loss tangent) than water in the frequency range [2GHz to 10GHz]?

thank you

If you are looking for absorber materials (which have very high losses), you can take a look at ECCOSORB or similar absorbers.

Body tissue
http://transition.fcc.gov/oet/rfsafety/dielectric.html

Also many other materials can be made lossy, like concrete, brick, etc., wet wood planks, etc.