Ancient Steel

Doing it the old fashioned way, creating blades from the earth
Material selection is everything.  Modern steel is the result of millennia of advancements on the first materials produced by the humble furnaces of our distant ancestors.  I addition to traveling the globe to study historic blades I felt that my knowledge would not be complete without an understanding of the steel used in those blades, steel very different from what we have today.

In the ancient world, before men created blades they had to make the steel from the raw ore.  The methods of going directly from the earth to fire to create metal is known as the “direct process” of steel making and, until it was replaced by the blast furnace in the late renaissance, was the way most steel was made.  I could replicate the shape and dimensions of the ancient blades, but until I worked with the steel the ancients used I would never truly understand their methods of blade making.

The first obstacle I encountered in making ancient steel was finding a source of raw materials. I could simply buy iron bearing materials but that sort of defeated the purpose.  In the ancient world whole cultures grew up around where the richest metallic ore deposits could be found.  Fortunately where I live turned out to be a distinct advantage.  Due to ancient volcanic forces which formed it, Michigan’s Upper Peninsula is one of the richest metallic ore spots in earth, so I began my search there.  A several hour drive north from Matherton Forge are the rugged and remote shores of the biggest and most forbidding of the great lakes, mighty Superior.  I knew Gitche Gumee’s relentless icy waves would have the power to tear lose the secrets the rocks held.

smelt04Walking the windy shores I soon found what I was looking for, streaks and patches of pure black sand that felt distinctly heavier than the surrounding beach sand.   A magnet quickly confirmed that this was rich magnetite iron ore.  This was the most convenient raw material, and was indeed the material that the ancient Japanese smiths used to create their steel, but I wanted to follow the path my ancestors used in creating the western swords I was fascinated by.

For a couple years I explored the more remote areas of northern Michigan, intentionally avoiding the commercial mining operations to smelt02obey trespassing laws as well as keeping it personal and real for myself, until I found the natural outcroppings I was looking for.   In vast areas of the old Marquette mineral range the earth is made of hematite ore but, here and there, thin veins of pure magnetite erupt to the surface forming whole rock faces that will grab a magnet.  Either of these ores would make excellent raw material.

Now the work began.  Magnetite sand is most convenient, and ready to go directly into the iron smelting furnace, but the rocky ores I wanted to use have to be roasted to facilitate hand crushing them into a very fine gravel.  Once the materials were ready I once again searched the ground of Michigan for the right clay to make my furnace.

smelt09smelt11The direct process does not produce molten metal like modern methods, instead it uses the chemistry of a carbon rich charcoal fire to separate pure iron particles from the ore and, under just the right conditions, add some carbon to it to make steel.  These particles gather in a porous mass in the bottom of the furnace known as a “bloom” giving the material the name “bloomery iron.”  This bloom is then hammered to squeeze the unwanted silicates out and weld the voids shut into a solid mass.  I then take extra steps to fold and forge the steel back onto itself several times to evenly distribute the carbon and homogenize the material.

In working with this very unique ancient material I have discovered that its properties diverge enough from modern alloys that it allows for a very different approach to bladesmithing than most understand today.  Many areas of hand working methods, blade design and heat treatment on ancient blades all make better sense now, and simply do not directly transfer over to modern material.

 

Back To the Sand

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I didn’t entirely abandon the idea of working with the sand I found on the shores of Lake Superior.  It was, after all, a very rich mix of magnetite and hematite, that was ready to smelt and just lying there waiting for me to scoop it up by the bucket.  On one occasion I invited my friend Tim Zowada to join me in a sand smelt, about which he wrote an article for the book Knives 2012 which and, as Tim claims, got him hooked on making bloomery steel.  The sand produces a bit more slag but also a fairly good bloom as well.

 

 

The Matherton Forge Iron Age Challenge

smelt15smelt14In the summers of 2009 and 2012, I held what I believe were historic events at my shop which I titled “The Matherton Forge Iron Age Challenge” where, in three day’s time, I took raw ore to a sword blade, capable of cutting a target.  While I admit it was great fun to do while spending time with all my bladesmithing friends, that level of physical expenditure showed me that I was no longer as young as I thought I was.