Aluminum for grounding and bonding?

I use a large aluminum sheet for my station ground plane and an attached aluminum buss bar.  So yes, aluminum can be used for your grounding needs.  I still have copper strap out to my copper grounding rods however.  The big drawback of aluminum wire is its tensile strength is about 40% less than copper wire, so it is more likely to break.  But with limited runs and the ability to visually inspect your connections, aluminum wire should be fine.  I don't think a larger guage would be necessary.  

Brad, AB4BA