Timo,

Yes.. I'm aware of crucible steel/wootz... sorry I should have been more clear. I'm mostly referring to the European arena in the context of my questions. Celts/Vikings/Saxons..etc.

AFAIK, crucible steel type technology wasn't used in Europe until the Industrial Revolution (e.g., English crucible steel).

It looks like we are having a break down in communication. :-)

My question was about the use of cast iron to make steel and it if occurred in European iron making scenarios. I was just responding to Kurt's statement that cast iron was used in this fashion. I've always heard that cast iron was rare and considered useless and not used in this manner in the times and regions I'm interested in. I wasn't considering wootz/crucible.... as I'm fully aware of where that was made. I'm just trying to get an understanding of how Celts/Vikings/Saxons, etc made steel... if it wasn't made directly in the furnace like the Styrian/Noric steel. If it wasn't made in the furnace then was it carburizing wrought iron via 'cementation' type methods, or 'orishigane' type techniques, etc.

Sorry, didn't yet have time to get into my literature. The iron produced in Noricum was with a high carbon content, but not cast iron, the temperature was too low. Mixing irons with higher and lower carbon content was quite common in Europe and elsewhere. A friend told me that a Saxon sax that had been send for polishing to Japan was found to have been manufactured after a similar technology in a way associated with their most advanced know-how. As I said, more to come, but at the moment I don't have much time.

The test on the seax you mentioned were done by Dr. Stefan Mäder using a polishing technique called "opening a window".
Some short articles with the results can be found online, but alas only in German.