Re: jasper? or agate? both? or not
What you have there is a brecciated jasper nodule that has been re-cemented after it was broken into pieces. It is very similar to chapenite from California:
I am not aware of any Spencer in Wyoming. Most likely you are thinking of Spencer Idaho on Interstate 15 near the Montana border.
From jay bates - August 27, 2010 at 08:28:19