So, I read a while ago several threads about making iron objects/blades from blood. In my conworld there are giant predators that would, according to my calculations, have enough blood so that 12 of them would make a decently sized sword (though that was counting the organs and all — would go up to 24 with just haemoglobin). This would mean that regular/anniversary hunts for such giants could lead to enough blood being stored for a royal (or very high born) person to have a sword forged for when they become an adult. I'm going off the basis that they are made aware by someone that there is iron in blood but that this person doesn't really influence their tech at all.
So the question is: how would you go about — with a people that barely are at the iron age — extracting iron from blood? I understand you would have to boil off the liquids from the blood and then turn it to ash but if I understood correctly the most tricky part is to decompose the haemoglobin and release the iron. So, with as much precision as possible, what process would be needed to properly extract the iron in order to make it into workable slugs? Would simply heating it all up degrade the haemoglobin enough or not?
Agrajag commented that centrifuging the ash and then recovering what is at the very bottom would give what I assume to be iron oxide (since they then advised that chemically reducing the powder would be needed, adding it needed to be mixed with equal part powdered natural graphite or ground charcoal and heat in the absence of an air flow). So: how hot would it need to burn to get the right type of ashes? How fast would it need to spin to get the iron to fall? And could this be replaced by some sort of decantation? And finally, is it needed to have graphite/charcoal, especially in equal parts, or is it like iron oxide/ore where you'd need at least a bloomery if not an actual blast furnace to change it to workable iron? And so would any kind of fuel work? I'm thinking of bamboo being used for wootz/damascus steel.
Thanks a lot!