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Jasper Whetstones

An Overview of Jasper Whetstones

Jasper sharpening stones are naturally extremely hard, abrasive, opaque to semi translucent and with high density. The material is highly sought after for its use in finish level sharpening. This Extends to hunting knives and home cutlery—straight razors and barbers cutthroat razors, axes, machetes, woodworking tools ect. especially on Edge Pro and Hapstone sharpeners. Jasper Stays dead flat when you sharpen which ensures precision level honing, and saves you the pain of your stone dishing out. To ensure the safety of the user, a razor sharp finish is always ideal. Sharpening artists using guided systems can mount the jasper whetstones on aluminum blanks as well from our selection of standard sized Ancient Ocean Jasper

Jasper is a micro crystalline quartz structure made of fused crystal grains that vary in sizes and shapes. In terms of chemical composition, the material consists of a higher percentage of hydroxides, iron oxides and silicates. Jasper has microscopic gemstone content as hard as a 7.5 on the moh's hardness scale, and the binder of the stone is compact and impervious to gouging even with very hard super steel.

Maintenance of Jasper Whetstones

Due to their high abrasion, abilities combined with hardness, jasper loads up with steel as you sharpen. How the stone is dressed makes it a coarser or finer whetstone. Jasper is very low maintainece and requires far less care than man made whetstones because it doesnt dish out. So when you want to refresh the cutting speed you can clean it to dislodge metal, or dress it again with an abrasive grit level of your choice. I find slurrying jasper with a 325 grit diamond plate that is worn in provides an excellent sharpening feel that gets very fine as it is worn in.

What is the Grit of natural Jasper Stones?

This a common question when using natural sharpening stones. The best answer is that when grit rating natural sharpening stones, you need to have a fair bit of prior experience so you have something to base your ratings on.   

When jasper is surfaced finely or well used and burnished with steel, it can hone as fine as a 30,000 grit finishing stone and above. Yet when jasper is freshly dressed with a lower grit it behaves more like a 1000 or sub 1000 grit stone. This stone is harder and denser than what most people feel when sharpening on a man made 1000 grit stone, so sometimes having both is handy. If you want to budget, just buy 1 jasper stone and it can be made dual grit sided. One side will just need to be cleaned or sanded lightly again on occasion to free it of metal, the other side can be your polishing stone. This aspect of changing surface dressing for a change in grit rating confuses some people, but the best way to explain it is this;

When jasper is dressed with a rough grit, more of the grit of the stone itself is exposed which lets it cut faster. As the stone loads with steel it gets finer and thus it sharpens at a higher grit. I won't flat out rate jasper and 1k grit or 30k grit because of this. This property is extremely useful and allows you to make sharpening very simple. As mentioned in many writings on my website, sharpening is best broken down into 3 stages, coarse grinding work, semi fine sanding / burr removal and then fine polishing / honing. Because jasper can quickly sharpen at a fine level, in my personal honing these days I just use a 325 grit diamond plate if I need to do extremely rough work, OR if im camping and I only have jasper with me I use one side of my jasper stone dressed with 80 or 120 grit so that it exposes a lot of abrasives and can handle fixing a dull edge. For most normal sharpening sessions I can use this side, OR a 1000 grit man made stone (I recommend Naniwa Chosera). Then for an impressive finish on a knife, or for sharpening a straight razor to shave with I go right from that 1000 grit level to the finer side of my jasper. A common technique I use is slurrying my jasper with a worn out diamond plate, preferably 325 or 600 grit. This slurry releases a ton of pure and ultra fine abrasive from the jasper. (diamond is harder than jasper so dressing the jasper with it cleans the metal from the pores and also releases fresh grit to work with). The ideal consistency is a milky white slurry, it turns this color because of pure silicate abrasives and gemstone content released from the stone. Working this slurry will take a 1000 grit ballpark edge straight to finishing level, allowing you to skip spending $500-1000 on a ton of mid range stones (2k-10k). This technique lets me just use a 325 diamond plate for stage one, a double sided jasper stone, or a 1000 grit stone for speed and ease and then jasper to finish. 

Now that we've talked free hand sharpening lets briefly cover Guided Sharpening Systems. In my shop I cut stones that are 4x1x.25" as well as 6" Lengths. These stones are precision made and designed to drop right into KME, Hapstone and Wicked Edge guided systems. Id recommend not gluing the stone to an aluminum blank because then you can still play with texturing one side of your jasper coarse and the other side fine.

Why Do some people use Aluminium blanks on Jasper Sharpening Stones for their guided systems?

  • Aluminum is impact resistant —so if your jasper accidentally falls on the floor the, chances of breaking the backing mount are pretty low. Jasper in and of itself is also impact resistant, but do take care not to drop it from a height of more than 5 feet.

  • Mounting the stone can make insertion into guided clamps easier, but we make sure the ends of the jasper are cut square and the faces of the stone are cut perfectly parallel so you don't need to mount if if you don't wish to.

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