2-3"
Random pull 
Your piece will be (if not the exact picture) quite similar!
 
Kambaba Jasper, sometimes called Green Stromatolite Jasper, contains swirls and orbs of deep green and black; one of the more exotic Jaspers. It contains the earliest records of life on Earth, fossilized algae and other primeval microorganisms, and is a marvelous stone for bringing peace and tranquility to troubled minds.
 
Please see our Crystal Lore Section for more info on this amazing stone!