Is this stone suitable and what grit might it be?

A friend of mine recently gave me half of a double sided stone. He had it for honing kitchen knives, not razors. It was broken in half when dropped, so he thought I might be able to use it.

Is it likely to be suitable for razors? It certainly needs lapping, but I'm happy to have a go at that.

If it is likely to be suitable, how can I figure out what grit each side is?

I'm posting some photos, in case they give any clues.

likely not suitable.. likely under 1k, and the darker side that looks coarser probably is. you might get lucky, the fine side might be a decent bevel setter, but again, probably not.