Stone age tool or just a rock? See photos

Many rocks have cleavage planes... meaning that because of the way the molecules bond to each other, they tend to break along specific flat surfaces and these flat surfaces tend to be along specific angles.

I am guessing that these rocks are naturally formed and that you are seeing an example of geological cleavage.

I think Farmerman would be a good person to confirm or contradict this.

Chris, agree w Max , for whatever that's worth, and looking fwd to Man's response

These guys are on the ball

Thanks for the quick reply guys, thought it was a bit of a long shot : ) Must admit, the geology side of it interests me.

Even though that rock has an edge it's unlikely it's sharp enough to be of any real value as a cutting tool. Most stone age tools which were used for cutting were some form of flint which forms a very sharp natural edge when split. That rock doesn't look like flint, so I doubt it was modified as a cutting tool.

That being said, it's not impossible that it's a much more primitive stone tool. The most ancient of stone tools were probably just rocks with coincidentally useful shapes. Rocks which didn't need to be modified at all and were used just as they are. This could have been used as a stone age tool even if it wasn't manufactured as a stone age tool.

Reminded of the BBC "Hitchhiker's Guide" movie,

"Address the chair!"

"There isn't a chair, there's only a rock."

"Well call it a chair!"

"Why not call it a rock?"