Not used for razors yet, but I just "harvested" another dozen or so stones to lap. I have tested the edge from these and it is suitable for razors! I will update with more progress and pics as I go along with razors on these. Mostly using the grey one now.
So I have been hell bent to try and source some stone locally that can serve as a sharpening stone. I have collected a few pieces over the last month or so of rockhounding twice a week. I am not a geologist, so all I can conclusively tell you is that they are indeed rocks.
First one is hard, very very hard! It chipped out my Estwing rock hammer severely and took almost 7 hours of hand lapping with a 220# diamond stone to get a reasonably flat surface. It has a soapy feel to it, hard as can be, slow stone.
The next one is a very fine stone, it feels like an 10K stone at first but building a slurry it quikckly slows down and works like a much finer stone. It needs a 30 minute soak seems like. It cracked across the face once I started lapping it, so I won't be able to hone razors on it, but knives are no problem. It is slower that the other stone, but softer and leaves a finer polish with self slurry.
I was unaware of how I should use these stones, at worst they will end up in the fish tank! I did some experimenting with various steels, kitchen knives, pocket knives, plane blades, hard steels to soft steel. These two rocks didn't gouge like the others I tried, the grit seemed fine enough and uniform enough to work, so I pretty much just went with the flow. I am not a very good freehand knife sharpener, but I can normally get a very sharp edge on all my knives, and edge bevels are pretty consistant, but not perfect. so this was good motivation to learn freehand sharpening.
The knife I really tried to work on was a wood workers marking knife I made a year or so ago. It is 1080 steel, ground, heat treated and sharpened by me. It has excellent edge retention, is not a super tough steel, easy to sharpen as well.
Here is a shot of the edge after using the black stone only, it polishes up nicely!
It took about 15 minutes to take the working class edge and get it to hair popping sharp, but I wanted to be able to whittle hair from freehand sharpening! I focused on my blade angle, consistancy, pressure, water on the stones, my breathing, and everything else I could think of. The knife is chisel ground with a slight URA grind on the back side. No stropping, no nagura stones, nothing but the edge it had and these two rocks! I finished the blade on the black one and used the white for some corrective passes.
A few mintes later and testing the edge it will now whittle hair along its entire length of edge!!!
I am soo happy that I have been able to do this! Not just find suitable stones, but to freehand sharpen to this degree has been very satisfying. Any and all educated guesses on the rocks would be appreciated.
-Xander
So I have been hell bent to try and source some stone locally that can serve as a sharpening stone. I have collected a few pieces over the last month or so of rockhounding twice a week. I am not a geologist, so all I can conclusively tell you is that they are indeed rocks.
First one is hard, very very hard! It chipped out my Estwing rock hammer severely and took almost 7 hours of hand lapping with a 220# diamond stone to get a reasonably flat surface. It has a soapy feel to it, hard as can be, slow stone.


The next one is a very fine stone, it feels like an 10K stone at first but building a slurry it quikckly slows down and works like a much finer stone. It needs a 30 minute soak seems like. It cracked across the face once I started lapping it, so I won't be able to hone razors on it, but knives are no problem. It is slower that the other stone, but softer and leaves a finer polish with self slurry.



I was unaware of how I should use these stones, at worst they will end up in the fish tank! I did some experimenting with various steels, kitchen knives, pocket knives, plane blades, hard steels to soft steel. These two rocks didn't gouge like the others I tried, the grit seemed fine enough and uniform enough to work, so I pretty much just went with the flow. I am not a very good freehand knife sharpener, but I can normally get a very sharp edge on all my knives, and edge bevels are pretty consistant, but not perfect. so this was good motivation to learn freehand sharpening.
The knife I really tried to work on was a wood workers marking knife I made a year or so ago. It is 1080 steel, ground, heat treated and sharpened by me. It has excellent edge retention, is not a super tough steel, easy to sharpen as well.

Here is a shot of the edge after using the black stone only, it polishes up nicely!

It took about 15 minutes to take the working class edge and get it to hair popping sharp, but I wanted to be able to whittle hair from freehand sharpening! I focused on my blade angle, consistancy, pressure, water on the stones, my breathing, and everything else I could think of. The knife is chisel ground with a slight URA grind on the back side. No stropping, no nagura stones, nothing but the edge it had and these two rocks! I finished the blade on the black one and used the white for some corrective passes.
A few mintes later and testing the edge it will now whittle hair along its entire length of edge!!!

I am soo happy that I have been able to do this! Not just find suitable stones, but to freehand sharpen to this degree has been very satisfying. Any and all educated guesses on the rocks would be appreciated.
-Xander