Translation of Japanese characters on blade of this higonokami?

[KHarper]

Can anyone tell me the meaning of the three characters on the blade itself?

I suspect they have to do with the type of steel in the blade, since I see the more expensive "Blue Paper" steel ones have different characters on the blade.
I gather from various internet sources that the characters on the handle mean:
1: "Registered Trademark" (four small characters in a square),
2: 3 larger characters below that mean "Higo No Kami",
3: the fourth character is a mystery, apparently pronounced sada
5: last one that represents the maker, Nagao Seisakujo, and is pronounced "kanekoma"
https://www.reddit.com/r/translator...o_english_the_handle_of_a_higonokami/?depth=2
So how about the three on the blade?
https://www.bladeforums.com/threads...mean-higonokami-knife-handle-writing.1271039/
An old thread about the characters on the handle, which is kind of hard to follow and doesn't show the characters properly.
Cool article on how higos are made: http://rudolfdick.com/wp-content/uploads/2016/04/Higonokami-English.pdf

 

[knarfeng]

FortyTwoBlades
As you are the vendor, do you happen to know?

 

[aboynamedsue]

Can anyone tell me the meaning of the three characters on the blade itself?
I suspect they have to do with the type of steel in the blade, since I see the more expensive "Blue Paper" steel ones have different characters on the blade.
The first character is very faint but you are correct.
It's 本割込 (HONWARIKOMI) that uses a carbon tool steel (SK steel) .
本(HON) means "Real" and "Genuine" or "Traditional".
青紙割込 (AOGAMIWARIKOMI) is the naming for the warikomi with "Blue Paper" steel.

 

[miso2]

"割込" (the last two letters) means clad steel or the way the blade made.
"本" (the first one) means "true" and in this case that the core steel extends all the way from the edge to the spine.

 

[FortyTwoBlades]

FortyTwoBlades
As you are the vendor, do you happen to know?

I don't know Japanese and their US distributor doesn't provide translations.

 

[KenHash]

When a double bevel blade is made using a core steel with a softer cladding, it is called "Warikomi"". 割込。
In the US this is basically what is known as "San Mai".
The Hon 本 before the Warikomi simply means genuine or true.
When the same core/cladding method is used on a single bevel knife, it is called Kasumi 霞.