cleaning up the slant six head

I know this proves nothing but Dan had me questioning what I thought I saw so I risked the possibility of melting and went out in the rain with a sharp razorblade, picked a spot on the head that was clearly cast iron ( machined surface of valve cover ledge ) and dug down deep with the blade.

Picked up the splinters and shards of cast iron with a magnet.

I know that someone will think that this is gasket material impreganted with just enough metal that it would stick too a magnet but there is nothing more I can or am willing to do to prove my case.

Just be careful everyone and have fun!

Id still sure like to hear a scientific explanation for this if anyone can come up with anything. Gotta be an answer.