Bow drill fire making tool

[Steven Saffold]

I found this on the beach (the stone) that should work good to keep the drill at bay. I dont think its an artifact.
http://i26.photobucket.com/albums/c120/richardsaffold/Primitive009.jpg

 

[bloodline]

I use something similar but it isnt as symetrical as yours.

(i want that one)

 

[Seagull]

Steven, I,ve found a lot of such stones on the Holderness coast .
I believe , but dont know for sure, that most of the rocks which end up on that coast, are
debris from glacial deposits.

Got one in garden, as a mini bird bath,...more like a bird eye-bath.

Often wondered how they came to be that way.

Any "Geo,s" here?

Ceeg