Both mine had olive green loose stool for the longest time - it's still the same color. Pedi says it's normal - just like kids, every poop is different.
Green is a "normal" color for baby poop. Red, white and black are the call the pediatrician colors. Green means that there is stomach bile in the poop, which just means their system is running a little faster than normal.
Re: dark green loose stool
Oh, thanks Massa. DD just started iron drops yesterday and her stool is crazy dark green...I didn't know why.