New Natural African whetstones - followup
Hi Folks, (long post, picture heavy)
It's been a while since I've posted anything, having been completely occupied with finishing my design thesis (it went very well). But so I wanted to post about my latest adventures in hone-hunting here in my neck of the woods (SA). Some may recall my previous post on the 'Silkvein' hones that I came across, and actually at that time I had uncovered other new specimens that I've been really excited about, and so here I wanted to share it all with you guys, in the interest of discussing the properties of natural honing stones.
Firstly I'm no geologist, just a guy trying to make sense of terms and properties of stones that I learn from reading this and that, so please share any knowledge you may have on anything in this post.
Basically from my research into the geology of Kwa Zulu Natal (where I live) we have what's called the lower Ecca shale formation, which is some 250 million years old. This shale varies greatly, and is in many cases more of a cherty/shale structure, with iron oxide being present in the mix, giving a very red/orange natural 'skin' to the sides of some of the stones. There are shales that break through the surface of the ground and this shale is courser/easily crumbles, more sandstone-y, but then 15m and deeper beneath the surface, as well as some shale being in contact with intrusive dolerite dykes or sills, the shales are much harder/finer - this 'indurated' shale is where my interest lies, and is what I think I've identified in my new collected specimens.
The stones I've found sort of look like Japanese naturals, and from what I've read about the makeup of Jnats, they certainly are indurated, cherty shales(Please correct me if I'm wrong), some harder/softer than others, presenting a variety of different elements in their matrix, resulting in the beautiful varieties available.
In a way, I guess I'm asking, could there be a geological link between the stones I've found and Jnats? The world is a big place, and geologically there must be overlap here and there with regards to formation age, climate, and the properties of these natural meta-sedimentary stones.
Now, in some of the stones, you will see the orange 'skin' on the underside and sides of the stone, (just like on jnats) which is iron oxide(a natural abrasive interestingly enough). But you'll also notice most of the stones have a fine speckled dot pattern on the surface, and to me this looks strikingly similar to close-up images of the Tam o'shanter/scotch hones. (Which I believe are also indurated shales to some extent or another..) So it certainly feels like we're in the appropriate 'hone territory' here - wouldn't you agree? ... please, if you guys that own natural scotch hones could let me know if the dotted appearance in my images is similar to your hones, I don't own any scotch stones, so I've only seen images posted here on SRP.
I believe they are all in the 8k range, some higher for sure, based on tongue and tooth feel tests...(crazy fool I know) But I do think it's hard to tell without thoroughly testing them with a range of razors.. as sometimes a natural stone will feel not as physically smooth to the touch as another, yet it will yield a finer scratch and sharper edge when used.. So it's all yet to be properly established, as I've not had the time nor appropriate broad knowledge of hones to test them myself.
This is a long ramble of a post, my apologies indeed.
But what more can I say. I've been loosely grouping them into similar piles, but there are at least 3/4 distinct types that I've isolated. In the images you'll see two roughly cut large pieces(these two are very fine indeed), which I'm very excited to cut up, one will be a MASSIVE hone for my private collection.
The wedge shaped piece was taken from the smaller of these large chunks, this is the stone that is greeny/grey with red streaks throughout.
Here are images I took today of the selection as described above. PLENTY OF PICS, because we all love pictures.
Thanks guys for letting me babble, hope it strikes up some discussion on hone stones, and perhaps some insights into what my specimens may be - geologically.
Sincerely
- Mike
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