For instance, American Novaculite (aka Washita and Arkansas Stones) is a form of metamorphic Chert that produces some of the best known and best loved natural whetstones in existence. Then, there is a form of Belgian Coticule which has been known for providing extra-keen edges since Roman times and, there is a Japanese Siliciclastic sedimentary stone (aka Japanese Water Stones) which consist of a fine silicate particles suspended in a clay matrix. Plus, there are also various types of man-made whetstones available such as Silicon Carbide (aka Crystalon) stones and Aluminum Oxide (aka India Stones) as well as a synthetic Corundum (aka Ruby) rod and Aluminum Oxide impregnated ceramic rods as well as several different types of diamond hones.
A: Most chefs have their own personal favorite and that’s what it comes down to for just about everybody; personal choice. If you’re the kind who likes to get personally involved in the process you might want to opt for a stone or stick knife sharpener.  These will allow you a certain amount of satisfaction knowing it was your expertise that produced the razor sharp edge. Others, however, are quite content to let the machine do the work and that’s fine too.
One of the most well-regarded natural whetstones is the yellow-gray "Belgian Coticule", which has been legendary for the edge it can give to blades since Roman times, and has been quarried for centuries from the Ardennes. The slightly coarser and more plentiful "Belgian Blue" whetstone is found naturally with the yellow coticule in adjacent strata; hence two-sided whetstones are available, with a naturally occurring seam between the yellow and blue layers. These are highly prized for their natural elegance and beauty, and for providing both a fast-cutting surface for establishing a bevel and a finer surface for refining it. This stone is considered one of the finest for sharpening straight razors.[citation needed]
The type of stone refers to the material it is made with. You can find many different types, including diamond, ceramic, natural stone, and synthetic. I would only suggest diamond if you’re planning to be sharpening only ceramic knives. Many of the stones you’ll find on Amazon or other retails are made of Corundum, which is a crystalline form of aluminium oxide. It’s a fine choice for a beginner sharpening stone.

Method 1: Use an Electric Sharpener. Quality electric sharpeners are an option, but I strongly discourage their use. First off, they remove a tremendous amount of material from your edge. Sharpen your knife a dozen times, and you've lost a good half-centimeter of width, throwing it off balance, and rendering any blade with a bolster (i.e. most high-end forged blades) useless. Secondly, even the best models provide only an adequate edge. If you don't mind replacing your knives every few years and are happy with the edge they give you, they'll do the trick. But a much better choice is to...
Very interesting. If you work flat, 45 degree is what I was taught. Love the wet stones, especially the oiled ones. The nice thing about the leather part, is the mirror finish on a razor sharp blade which is a must if doing fine wood working, carving etc. A rough blade simply does not have the fine detailed dexterity. I find that the oiled sandpaper can work great as well, but found that the refined clay bars (white refined fired clay rounds and flats etc) does a wonderful job of keeping those razor edges refined, smooth as possible and then one can high polish them for smooth cutting. Believe me, when working wood for a flute, one wants that refined edge.! Learning how to hone a blade on a flat surface teaches one to work outside without a table/wall handy too...:) But we all have to start somewhere!:) Anyway, great stuff and a great start for those who want more from their tools!:) Cheers!

This wedge ends up short of a "point" to a much larger degree than the picture would indicate. The metal stops short, but then there is black non-slide "tape" applied to one side, and white "slide" tape applied to the other side, which makes the wedge even thicker than it appears in the photo, which means that in practice the end of wedge is even more truncated. So I have a hard time supporting my knives accurately on this wedge while sliding them down into contact with my stones. Prior to buying this wedge I just used a wooden wedge I cut off of a 3" by 3" post using a miter saw, said wedgewhich has a much less truncated end. That wooden wedge unfortunately absorbs water from my Japanese Waterstones. But I will try spraying polyurethane on that wooden wedge to help waterproof itand try again. If that doesn't work I will try to find a 3" by 3" plastic trim board somewhere and cut a wedge off the end of that. Note that you can buy 20 degree plastic wedges, but this is the first one I have found that does 15 degrees (nominal.) Note that Amazon also has the Blue AngleGuide set of wedges, but they are very small
Next we sharpen the opposite side of the blade. Just as you did before, sharpen the knife keeping an angle of 10' to 15'. Push the point you want to sharpen with your first, second and third fingers. While keeping the angle and pushing the point with your fingers, stroke the blade until it reaches the other edge of the whetstone. Then pull the blade back until it reaches the edge of the whetstone. This back and forth is counted as one stroke. Repeat it for about five strokes until you can see or feel some small burrs (edge curvatures).. Then move the position of your fingers to where you have not sharpened yet, and repeat this five strokes of sharpening processed from the tip to the base of the blade. When your whetstone becomes dry, occational watering during  sharpening process will also help and improve smooth sharpening.
using an appropriate blade for the task – a thinner blade for more delicate work, and a thicker blade whenever a thinner blade is not required (e.g. a thinner blade might be used to cut fillets, butterfly steak or roast for stuffing, or perform Mukimono, while a thicker one might be used to slice or chop repeatedly, separate primal cuts of poultry or small game, or scrape and trim fat from meat or hide, as these actions would be more likely to cause unnecessary wear on a thinner blade.)
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.
Clean the knives and stone. As soon as you've finished sharpening your knives, wash and dry the blades. You should also clean the stone according to the manufacturer's instructions. For example, if you have an oil stone, you might need to scrub it occasionally with a stiff fiber brush and soak it in oil. For a water stone, wash off any of the residue and store it in a dry cloth until you need to use it again.[11]
I purchased this set together with the 400/1000 grit stone assuming that some of my knives were quite dull and would need work on a coarse grit stone. Premium Whetstone Sharpening Stone 2 Side Grit 400/1000 | Knife Sharpener Waterstone with NonSlip Rubber Base & Flattening Stone. This is my first wetstone. First off I tried to sharpen my Chicago Cutlery boning knife. This knife is nearly thirty years old, has been abused in may ways and was quite dull. It was very difficult for me to get a burr on this blade, which I attribute to poor technique. Next I moved on to my Henckels Professional S paring and chef's knives. The paring knife was moderately sharp and was modestly improved after working over all three grits of stone. It would cut paper but again it was difficult to develop a burr with this blade. Undaunted I switched to the chef's knife. This knife is twenty years old and has never been professionally re-sharpened. I have sharpened it twice with a Lanksey sharpening system which marred the finish but did put a good edge on the blade. Lansky Standard Coarse Sharpening System with Fine Hones. The chef's knife was moderately dull and had several pits visible on the cutting surface. I modified my technique for passing the knife over the stone and worked the chef's knife over the 400 grit stone aggressively and eventually I was able to get a burr to form from the tip of the knife all the way to the handle. From there it was a simple process of reforming the burr on the 1000 grit stone and then finishing on the 6000. After sharpening, the chef's knife easily and cleanly slices a tomato with very light pressure and is in my opinion very sharp. Not sushi knife sharp but more than enough for the chopping and slicing I expect of it. I'm looking forward to going back and working both the boning knife and the paring knife over again. Don't expect a good result from this product the first time you use it. Watch videos on using a wetstone, expect to spend at least twenty minutes per knife at first, and practice forming a burr. If you can form a burr, you will be able to successfully sharpen your knife.