Making a hone

[HippieDave]

Here is something to look for in the wild, old slate roofing tiles. This one came from a 150 yr. old barn in S.W. Ohio and was most likely quarried in Pennsylvania. While it's only 1/8 in. thick I was able to cut 4 of them 3 in. wide from one tile.

I used this after setting the bevel on a King 1000. Lapped for 10 min. (about 100 laps per 5 min.)with a thin slurry (this is a hard slate to slurry) and got a tree topping edge. Finished on a blue/green Escher to HHT4.
My honing and SR shaving experience is a bit limited so I don't know if this would be a good finishing stone but for $3.00 I got 4 thin stones to find out with.
So keep an eye out for old slate roofing tiles. I'm sure our Great Grand Dads did.

 

[Mackis]

Nice find. Just stropped my razor and shaved, it was a good shave, i rushed it a bit and could have done a better job honing and stropping. Will do a new test tomorrow. Will post picture of my tile tomorrow and some from the edge with the usb microscope

 

[HippieDave]

Here's are two other "found in the wild" stones, both are kind of aqua blue/green and rough cut on one or two sides. I'm pretty sure they were cut from patio stones at one time.

They perform much the same as the roofing tile and are hard to slurry.
I had a wood shop teacher in high school who said his Father in law had a patio with a piece of green slate in it and he would always tell him "If you ever tear out this patio I want that green slate. Green slate is the best honing stone for wood working tools."
I don't think he knew he was talking about an Escher Thuringain.

 

[Mackis]

Nices hones you made out of them, are they all finishers?

I think you are lucky if all turned out to be good finishers. The other two slate samles i picked up originates from granit or gneis. They are slates and they are metamorf rocks but in a rough and hard condition. I will do some tests on them and se if i can use them as hones. The two small samples is from norway oppdal and ottedal i think the name was. Norway have produced god hones the vikings made use of its just a matter if it is the type we are searching for that can be used on razors.
I will lapp them up and test, i will also heat treat them and se how that affects the results.

The brazilian originates from silth and are from finer material. Under my simple microscope i can see the small particels of abrasive crystals.

 

[Mackis]

Here is an early image after the first flattening. It have woodlike pattern.
It is darker in reallife darkgray to lightgray. In the lite you can se small sparkels from the abbrasive particels.

 

[Mackis]

Ok made some more testing on the Brazilian slate, it could be a decent knife sharpener or used in a progression to a finish. I rate it between 1500-3000 grits, the striations is finer than my naniwa 1k pro and somewhat compareable to my kitiyama 3k. I will try it as a bevelsetter but i think it will be used for my kitchen knifes, i don't trust it for my finer razors. Maybe a GD or ZY razor can be set on this.