[Emanuel]

Here is an excerpt from Ann Feuerbach's "Damascus Steel and Crucible Steel in Central Asia" American Society of Arms Collectors Bulletin 82.

The microstructure indicated that this was a high-carbon steel which was slowly cooled. Electron probe micro- analysis indicated that it contained small amounts of other elements, including manganese. This is significant because one of the most famous Damascus patterns is called Kara Khorasan (black Khorasan). In order to form this pattern, the original bulat needed to be high-carbon steel with specific impurities that was slowly cooled.

p.38

After many experiments with different plants and other carbon-containing substances, he [Anosov] concluded that the form of the carbon was unimportant but the amount of carbon in the steel was crucial...He concluded that steel should be pure in order to produce a pattern. This we now know to be true up to a certain point, but we also know that trace elements are necessary (Verhoeven et al., 1998, pp. 58-64), but these need to be present in an amount which Anosov was not able to detect. He studied the effect of titanium, manganese, silicon, chromium, silver, gold, aluminum

and platinum. While performing these studies of alloys, he independently concluded that silicon effects the formation of graphite, that chromium increases the hardness and improves the finish and discovered the effects of other alloying elements....Anosov also discussed the characteristics of the shrinking phenomenon and the necessity of slow cooling for crystal growth as well as the necessity of repeated forging at low temperatures and the different methods of producing different patterns. Textual, archaeological, ethnographic and modern replication evidence shows that these methods can produce steel with a Damascus pattern. Anosov succeeded in producing Damascus steel swords with the characteristic pattern and properties, including swords that could cut silk in the air and bend to a 90 angle and spring back with no apparent structural damage...Anosov only lived long enough to publish an abridged version of his research. This paper, "On the Bulat", was published in the Russian Gorny Journal in 1841 and was translated into French and German in 1843

p.40

So the ore would have been important to the extent that it included trace amounts of manganese, silicon, phosphorus and other elements. These trace elements facilitated the creation of the dark bands seen in Kara Khorasan pattern. Greg Obach experimented with steels with trace quantities of these elements. See his results and decide if it's Khorasan or not

Simplistically then, we're discussing a base dendritic pattern in a high-carbon steel that is the result of the metal smelting process, through more or less slow cooling of a crucible charge heated to mostly liquid phase.

This is followed by a mechanical deformation of this pattern through the forging process, either by fullering, or grinding/cutting grooves into the blade. The grooves are flattened, resulting in the Mohamed's Ladder pattern. The same fullering process would be used on a homogeneous plain steel blade, you just don't get any pattern.

I guess the original Ladder pattern was simply the by-product of the drawing out process of the cake to a bar that could become a blade. A fuller may have been used at first to move the metal, while later grooves might have been cut into the bar on purpose to expose deeper layers and accentuate the patterns.

As far as I'm concerned then, Anosov understood the first step, producing the high-carbon crucible steel with visible pattern. He may not have known which trace elemental amounts were most effective at producing the darker contrast bands due to the technical limitations of his age.

Whether or not Anosov replicated the precise mechanical deformation in the second step is irrelevant to me. Modern smiths now understand both steps pretty well. Does the "secret" of whether you should strike the blade 40 times this way as opposed to 50 times the other way really matter?