Once the burr is removed, it's time to test the sharpness with paper. Hold a piece of newspaper at about 45°, with a bit of tension, and slash lightly with each point of the blade. If it cuts through easily, your knife's sharp. Warner speedily lacerated his newspaper, but I of course struggled. There is an element of technique involved, he reassured me.  

If no metal is being removed from the edge of the blade, it’s considered honing. Whereas if metal is being removed from the blade edge this is considered sharpening. Certainly, even honing will result in some microscopic amounts of metal being removed from the blade edge but not enough to be visible to the human eye, so the above definition is basically a solid one.
Mine came plain white then started to darken after a few weeks. About 4 weeks in it settled to a more natural stone/slate grey. The leather has darkened a bit too and remains soft and comfortable. The leather remains easy to adjust and my selected sizings stays in place firmly. Overall It feels, looks and works great. The knot and darker stone/leather compliment each other well.
Sharpening on the other hand is reupholstering the furniture or telling the hair stylist to give you a new look. Material is going to be removed from the edge of the blade. There’s no way around it. How much is removed will be a function of just how dull the knife has become or whether you’re sharpening to compensate for a chip in the edge or because the tip has broken off. If your knife is not damaged and you have it sharpened twice a year very little material will be removed each time, yet it may still be enough for you to notice just by looking carefully with the naked eye.
Begin with your lower-grit stone. Place the heel of your knife on the far edge of the stone, holding the blade gently but firmly with both hands at a 15- to 20-degree angle. Using even pressure, slowly drag the knife over the stone toward you down the length of the stone while simultaneously moving the knife such that the contact point moves toward the tip of the blade.
Before we start, I want to make clear that there are dozens of different ways to sharpen a knife. Everyone has a way they think is best, and men have all sorts  of techniques and tools that they feel are essential in getting a sharp blade. In the end, much of it comes down to personal preference. I’m going to show you the way I learned how to sharpen a pocket knife. It’s very basic, good for beginners, and best of all, it works. If you have an alternative method that you prefer, great. Share it with us in the comments. I’d love to hear your tips. 

Vielsalm Coticule on the other hand generally occurs in much more narrow layers sandwiched between the slate layer and the Belgian Blue layer and thus, it is both less plentiful and more expensive than Belgian Blue stone. Also, Coticule is divided into different grades and sometimes displays blemishes on the surface due to its proximity to the slate layer. Furthermore, it is somewhat harder than Belgium Blue stone and, due to its brittleness, it is bonded to a substrate layer of hard slate prior to sale to prevent the stone from breaking during use.

1. Diamond Stones. I’ve used two, many years ago, to sharpen steel knives & found that the diamond coating wore away. They did work well at first, but then I was sharpening on the backing material. This puzzled me, because diamond is harder than steel, but have only recently read that the diamond particles are torn off the backing material because they stick to the softer steel. Diamond stones are recommended for sharpening ceramic knives only. This info about diamond stones & steel knives I got from an Edge-Pro article.
Diamond hones are made from very small, industrial grade, diamonds adhered to the face of a metal or plastic plate. Also, because Diamonds are so much harder than any of the other sharpening materials, they tend to cut very fast and last much longer than the other whetstone materials. But, they are also often more expensive to purchase. In addition, Diamond Stones generally consist of three different styles consisting of a solid metal plate coated with an adhesive and diamond dust with holes in the plate to allow the swarf to escape, a solid plate without holes for sharpening tools with corners that might catch in the holes, and a plastic plate with islands of exposed plastic interspersed with the adhesive and diamond dust to act as a lubricant.
Furthermore, Novaculite consists of several different layers of stone of different densities, grit sizes, and colors. Thus, the red Novaculite layer (aka Washita Stone) is the both the softest and most coarse while, the next most coarse/hard grade is the grey/white Soft Arkansas stone; both of which cut relatively fast for a hard whetstone material and thus, they are an excellent choice for refining a bevel. Then, the next grade of coarseness/hardness is the hard Arkansas stone which is used to polish the bevel rather than define it and, last there are the grades of Hard Black and Hard Translucent Arkansas stones which are used for extremely fine honing and polishing of a cutting edge. Plus, it’s also the primary material in “Charnley Forest” (English) and “Turkey” oilstones.
The truth is that there is no one recommendation that we can make that will meet everyone’s needs. Every sharpener’s needs are different and every sharpening toolkit will be different. In order to help beginning sharpeners get started with good sharpening stones to build around, we need to understand their individual needs. So with that in mind, let’s look at the basic needs of a beginning sharpener.
As you probably have guessed, knives are easier to sharpen on longer stones. The width of the stone is less important than the length when sharpening knives. The longer stone allows for longer sharpening strokes and contributes to faster sharpening. The longer strokes mean fewer strokes across your stone, making it easier to maintain a consistent sharpening angle. As a rule of thumb, a small knife can easily be sharpened on a large stone, but a large knife cannot easily be sharpened on a small stone.

I recommend keeping two stones in your kit. One with a medium grit (around 800 or so) to perform major sharpening jobs, and one with a fine grit (at least 2,000) to tune the edge to a razor-sharp finish. For real pros, a stone with an ultra-fine grit (8,000 and above) will leave a mirror-like finish on your blade, but most cooks won't notice the difference in terms of cutting ability.
The newly designed dual-sided combination whetstone from Fallkniven features a super fine white ceramic stone (0, 1 micron) with a grit of 1400 to 2000 and the dark grey ceramic stone is made of synthetic sapphires (1 micron) and has a grit of 800-1000. There is no need to add any oil or water, just lay the blade on the stone, raise the blade's spine and deburr your blade on the grey side until it has a razor-sharp edge and then use the smooth white side to get a nice polished edge.
The newly designed dual-sided combination whetstone from Fallkniven features a super fine white ceramic stone (0, 1 micron) with a grit of 1400 to 2000 and the dark grey ceramic stone is made of synthetic sapphires (1 micron) and has a grit of 800-1000. There is no need to add any oil or water, just lay the blade on the stone, raise the blade's spine and deburr your blade on the grey side until it has a razor-sharp edge and then use the smooth white side to get a nice polished edge.
Silicone Carbide whetstones on the other hand, are the fastest cutting of the three types of oil stones and the stones made by Norton are called Crystolon Stones. Also they too are graded as either fine, medium, or coarse stones depending on their grit. But, although these stones will not produce an edge as fine as Arkansas Oil Stones or India Oil Stones, their fast cutting ability makes them ideal for sharpening tools as well as for cutting the initial edge bevel on extremely dull knives or repairing the edge on damaged blades. Last, because they sharpen so quickly, it a common practice to start with a coarse Crystolon Oil Stone and then progress to either a medium or fine India Oil Stone and then to finish with an Arkansas Oil Stone.

You might not need to spend hundreds of pounds to get the best knife sharpener, but you do need to know what you're doing. Warner gave me a crash course in the technique. As a newbie to this method, it took a while to get used to (especially since Warner handed me a knife that had never previously been sharpened) but after half an hour's practice and a little encouragement, I got the hang of it. Here's what I learned...
A diamond plate is a steel plate, sometimes mounted on a plastic or resin base, coated with diamond grit, an abrasive that will grind metal. When they are mounted they are sometimes known as diamond stones.[12] The plate may have a series of holes cut in it that capture the swarf cast off as grinding takes place, and cuts costs by reducing the amount of abrasive surface area on each plate. Diamond plates can serve many purposes including sharpening steel tools, and for maintaining the flatness of man-made waterstones, which can become grooved or hollowed in use. Truing (flattening a stone whose shape has been changed as it wears away) is widely considered essential to the sharpening process but some hand sharpening techniques utilise the high points of a non-true stone. As the only part of a diamond plate to wear away is a very thin coating of grit and adhesive, and in a good diamond plate this wear is minimal due to diamond's hardness, a diamond plate retains its flatness. Rubbing the diamond plate on a whetstone to true (flatten) the whetstone is a modern alternative to more traditional truing methods.[13]
When you sharpen a Buck Knife properly it will perform the way it was meant to. Never sharpen your knife on a power-driven grinding wheel not specifically designed for that purpose. You could burn the temper from your blade making the edge brittle and prone to chips or cracks. This also voids the warranty. The first step to knife sharpening is to pick a sharpener.
Historically, there are three broad grades of Japanese sharpening stones: the ara-to, or "rough stone", the naka-to or "middle/medium stone" and the shiage-to or "finishing stone". There is a fourth type of stone, the nagura, which is not used directly. Rather, it is used to form a cutting slurry on the shiage-to, which is often too hard to create the necessary slurry. Converting these names to absolute grit size is difficult as the classes are broad and natural stones have no inherent "grit number". As an indication, ara-to is probably (using a non-Japanese system of grading grit size) 500–1000 grit. The naka-to is probably 3000–5000 grit and the shiage-to is likely 7000–10000 grit. Current synthetic grit values range from extremely coarse, such as 120 grit, through extremely fine, such as 30,000 grit (less than half a micrometer abrasive particle size).[citation needed]
When sharpening a knife, you're actually grinding away the existing blade to create a new edge. This is evidenced by the fact that upon completion, you can find tiny metal filings, called swarf, when wiping down the stone. Because the metal blade is actually being ground away, a high importance is placed on the technique and consistency of drawing a knife over the stone.
Last, it should be noted that dual-sided Coticule/Belgian Blue whetstones are also sometimes available which have a layer of Belgian Blue stone on one side and a layer of Coticule on the other. Thus, these whetstones provide a softer, more coarse, grit on one side and a harder, finer, grit on the other. Plus, due to the inherent toughness of the Belgian Blue stone, these dual-sided stones do not require a substrate layer.