The white structures are most likely from tubeworms and indicate that the pipe was underwater for quite a bit of time. Many native American tribes made stone/soapstone pipes in the southwest.This one's air hole is three little holes near the bottom of the bowl where the draft hole is located. The air hole and the shank are clogged up with a petrified growth of something or another. I have no certificate of authenticity but the person who gifted it to me found it on his property in Arizona about 20-years ago. It's made of some kind of rock. Pretty, ain't it?