Thread: Japanese naturals - Finishing question

Originally Posted by alx

Yes, I have. Do you have any indications as to what is in the stone "chemistry wise" that would turn the slurry orange while honing steel, and why it will etch the blade at the same time?

Alx

It is by nature acidic, that is what etches the blade, and what makes the metal in the slurry to rust. Not all stones are equally acidic, some are more than others.

Originally Posted by mainaman

It is by nature acidic, that is what etches the blade, and what makes the metal in the slurry to rust. Not all stones are equally acidic, some are more than others.

I guess everything in nature is acid or base . Just depends on the degree as you say.

Originally Posted by onimaru55

I guess everything in nature is acid or base . Just depends on the degree as you say.

Lick the stone, see if it burns or tastes bitter.. science at its best :P

I've noticed after using some stones my blade can rust within an hour after if not treated correctly but never put it down to the stone, ill have to pay more attention to see what stones cause this.

Originally Posted by Brighty83

I've noticed after using some stones my blade can rust within an hour after if not treated correctly but never put it down to the stone, ill have to pay more attention to see what stones cause this.

That could be the steel too.

I figured it was the steel although i may keep an eye out to see if i can find something like this related to the stones rather then the steel, do you believe some of the stones have a high acidic content?

Originally Posted by Brighty83

I figured it was the steel although i may keep an eye out to see if i can find something like this related to the stones rather then the steel, do you believe some of the stones have a high acidic content?

I'll have to speak to my science teacher mate. He'll have a clue.

Originally Posted by alx

Yes, I have. Do you have any indications as to what is in the stone "chemistry wise" that would turn the slurry orange while honing steel, and why it will etch the blade at the same time?

Alx

Have experienced the same thing! With several razors, but only with my 2 Jnats, slurry is first grey and then gets orange... Then sticks on the razor... Like rust, maybe the Jnats are accelerators for rusting really fast? (sometimes minutes!)
The argument against it is that the staining on the blade isn't coming off so easily like rust would... Maybe the "acid" is also a fixator...?

Kindest regards

Originally Posted by Brighty83

I figured it was the steel although i may keep an eye out to see if i can find something like this related to the stones rather then the steel, do you believe some of the stones have a high acidic content?

Here's a few facts from my science teacher mate.

Abrading steel increases the chance of oxidation. Add water & this increases further.
The black slurry you see is also rust. Iron oxide can be red or black as we all know from looking at old razors.

The slurry colour may also be due to the composition of different minerals in the stones, possibly acidic . The minerals themselves e.g. Mica, can contain iron to further colour the slurry.
The steel itself is another factor to consider as some steels rust quickly.

Originally Posted by Brighty83

I figured it was the steel although i may keep an eye out to see if i can find something like this related to the stones rather then the steel, do you believe some of the stones have a high acidic content?

I have seen tests with Jnats that clearly show acidity of the slurry. The test was from a blog in Japanese.

Just for fun i purchased some PH and Alkalinity test strip, mixed up some slurry and wiped it accross a bunch of stone to see what would happen.

Top mark is Alkalinity (light is lower, dark is higher)
Bottom is PH (light is lower, dark is higher)

1 - Water Only
2 - Belgium Couticle
3 - Tam o Shanter
4 - Random Jnat 1
5 - Random Jnat 2
6 - Random Jnat 3
7 - Random Jnat 4
8 - Random Jnat 5
9 - Vinegar (Acidic results)




Whats interesting is there is a definite result on some stones although its base, not acidic. Infact, its strong on the base side of the chart.

I have ordered some new strips that have double the range to these, i would love to see how alkaline these are. I will grab some more stones next time as well!