Making steel in Aristotle furnace, 

The presence of the slag is necessary for the bloomery iron process. Running the bloom (refined ones) the second time in the bloomery furnace can cause the burning of the iron because the bloom would not be protected by the slag. The Aristotle furnace is the better solution to get carburized.

bloomery iron gromps are conglomerate iron and slag. A small amount of slag gives better results. You can use slack instead gromps.

Yes i used my own made iron. The alloy has about 1% of C.

@@officinaferraria cool.

You want cold air though, not hot. Sort of counter-intuitive, but cold air is denser, therefore has more oxygen per unit of volume. That’s what an intercooler on an engine is for.

The whole idea is to learn more about how certain processes were carried out by our forebears, the distinct process in this case, being the Aristotle furnace. Whether the bloom it is then struck by a power hammer or a striker with a sledge makes no real difference to the steel, but saves a great deal of time and effort ...... unless you prefer to watch a very much longer video .... ?

Mild steel is ok for that

In my smelting experiments, I use different types of ore (bog ore, siderite, hematite, and magnetite). In Poland, the most common is bog ore but siderite and hematite also can be found.