Thread: Question for you rock hounds.

So today I went to the house of one of my surfing buddies. He had a.stack of rocks I was admiring And I joked about that tendency that is a side effect of HAD where you look at random rocks and say, "Hey, I'll bet I could hone a razor on that."... Then I saw this one and actually did say that.


To which he replied that I should take it. At first I thought it was slate because it looked very gray in the shade but in the bright sun and looking at the little chips off of it...


...you can see that it is very green and has a very even sparkly mineral to it. I asked him if he knew where it was from and, as he is a bit of a hoarder, he said, "That might be from Alaska... Or from North Carolina. One of the two."
Sooo... I'm wondering if anybody has ideas of what it might be. I'm thinking maybe basalt from what I could see from pictures on the internet. It's very dense and very heavy for its size. I thought that I would smooth off that top side and lap it down. It also seems very hard and if nothing else it might be a good slurry stone.

Any ideas?

Edit: Oh, and also if you thought it might be good for honing.