Thanks to all for the feed-back.

The problem is that when I was there, the man only explained (in
Korean) what he did, indicating his equipment. I did not see him
actually working live (though he did simulate his hammering).

I only saw a video (from a national documentary show) of him in
action, and there was so much to see that went by so fast, so I can't
be positive that what I saw was actually molten though that's what my
notes indicate. The man uses the product (which he called in English
"pig iron") to repeatedly hammer and heat into steel which he finally
makes into steel sword blades, which are replicas of historic Korean
swords based on his museological, metallurgical and practical research.

'Any more comments?