Thread: The Black Polish

Thought this was cool. Copied it out of an old knife magazine. I'm guessing razors got this treatment too ?

" The Sheffielders called it the "Black Polish", a polish so gleaming, so bright that it appeared black at certain angles - and it was one of the finest polishes the world of cutlery has ever seen.
It came from slow moving wooden wheels with a lead surface and finishing compounds that included ashes mixed with beeswax. With the development of health standards in the workplace fewer factories would take time (or submit their workers to the risk) of producing the beautiful black polish."

The rest of the article mentions a Solingen cutlery factory that did the same polish up till 1956 when it closed. Bruckman was their name.

Would be something to see.

Very intersting! There is a brief mention of it here, too - on the 2nd page. It mentions "iron oxide" which I take to mean a very finely divided rouge which used to be called "crocus" - see this page for details - used for obtaining a mirror-finish.

I can understand the lead lining - soft compared to steel. Crocus is still available, but as it is sold more as a pigment for ceramics it's purity/grit size is a bit questionable, although I suppose a good grind with a mortar and pestle, slaking in water to remove the larger bits and evaporation would produce something usable.

Regards,
Neil

that is fine reading makes you like how easy it is to get a blade now.

Originally Posted by Neil Miller

Very intersting! There is a brief mention of it here, too - on the 2nd page. It mentions "iron oxide" which I take to mean a very finely divided rouge which used to be called "crocus" - see this page for details - used for obtaining a mirror-finish.

I can understand the lead lining - soft compared to steel. Crocus is still available, but as it is sold more as a pigment for ceramics it's purity/grit size is a bit questionable, although I suppose a good grind with a mortar and pestle, slaking in water to remove the larger bits and evaporation would produce something usable.

Regards,
Neil

Thanks for the link. That's interesting about the rouge. You can get superfine jewellers rouge powder for polishing glass etc. Japanese swords are polished lastly with a paste called 'Nugui' which is mostly some form of iron oxide plus other ingredients. The blade steel is somewhat darkened by the process to a bluish or blackish hue. I imagine this may be similar to the 'Sheffield black polish' except it is done by hand & very tedious. The red oxide makes for the darker finish whilst magnetite produces a more subtle finish called 'Sashikomi'. I feel some experimentation coming up

Good luck Oz! That fellow in one of the links took seven years to perfect his black polish recipe...

Regards,
Neil

Very interesting indeed. I always thought that "iron" oxide was pretty unstable and would readily become a hydroxide (upon reaction with water). I found this link stating the chemical formulas of several iron oxides and their color. The application, in this case is different but I felt that I would share this information with you guys here:

Iron oxides in cosmetics

And I just found this one as well, man this is pretty interesting:

Iron oxide - Wikipedia, the free encyclopedia

Al raz.

Originally Posted by Neil Miller

Good luck Oz! That fellow in one of the links took seven years to perfect his black polish recipe...

Regards,
Neil

3" of razor will finish a lot quicker than 28" of katana ~ believe me, I have done the latter

Originally Posted by Alraz

Very interesting indeed. I always thought that "iron" oxide was pretty unstable and would readily become a hydroxide (upon reaction with water). I found this link stating the chemical formulas of several iron oxides and their color. The application, in this case is different but I felt that I would share this information with you guys here:

Iron oxides in cosmetics

And I just found this one as well, man this is pretty interesting:

Iron oxide - Wikipedia, the free encyclopedia

Al raz.

Thanx Al but the oxide is traditionally mixed with Choji oil for sword polishing. I agree water sounds a bad idea

I owned a Wade & Butcher India Steel that if held at a certain angle to daylight , the steel had an almost blueing sheen- not unlike a gun barrel. In its time it was probably done with "black polish" like you describe. Damn fine old razor it was. I miss it now.

A bit more information I found re: lead wheels and black polish:

"...In Lapping Penknives and Small Articles, it is more usual to charge the wheel whilst it is at rest, by rubbing on it a lump of emery cake, made of emery compounded with suet chopped fine and rendered down, and mixed with a very little wax, sometimes the dressing is rubbed in with the agate or bouldering stone, and as before explained, to fine the lap, at the conclusion the head is rubbed off and it is smoothed with the agate.

When the lap is coarse and the work is pressed heavily it produces a white colour on steel, and when the lap is fine and the work is pressed lightly, and gradually drawn from the one end to the other it gives a black polish - to attain this end the emery is worn down fine with the work, and afterwards with the bouldering stone, and the effect of the emery is still more deadened by putting a little bees'-wax on the face of the lap, the smoothness of which is tried with the finger before applying the work. [...] Metal laps are under very different circumstances from grindstones or cement wheels, as the metal constituting the lap has no cutting power in itself, but only derives it from the particles of emery which become embedded in its surface and act as the teeth of a file. ..."

The article describes the wooden wheel covered with lead, as posted above, and goes on to say that the shank/tang of the razor was "glazed" using a wheel made from hard-wood, and that other parts of the razor were polished using a wooden wheel covered with thick, soft leather as is used in the soles of shoes (it is much softer before hammering). Bits of thick leather charged with crocus were also used attached to sticks to polish some parts.

Regards,
Neil

Thanx Neil. Any other info on the "agate or bouldering stone"