Oil Stones differ from water stones in that they require the use of honing oil to float the swarf (metal particles). Also, these stones are commonly made from one of three different materials consisting of Novaculite, Aluminum Oxide (Corundum), or Silicon Carbide (Carborundum) and they all use oil to lubricate the stone and suspend the swarf in order to prevent the stone from becoming clogged. Also, while Novaculite and Coticule are the most traditional types of oil stones, there are also synthetic oil stones made by the Norton abrasives company called “India Oil Stones”. 

To use a whetstone you run the knife's blade back and forth across the stone's surface and due to the constant friction with the stone, which acts like a piece of sandpaper, the knife's edge becomes razor sharp and has a brilliant mirror shine. If you are a beginner at using a whetstone it can a take a while to master the sharpening process, so here is a video to help you with your sharpening stone skills.
I had wanted a pair of sharpening stones for a while, so was enthused to get this last week. I watched a bunch of YouTube videos on how to use them and a deburring strop I also bought and wow, my kitchen and pocket knives are now wicked sharp. Pro tip: if you post anything about it on social media, family and friends will almost surely volunteer their knives for more practice...
Works well. Just got it today, sharpened two pocket knives, one a 8Cr13MoV Chinese steel, the other s30v American steel The stone made short work of both steels (which were pretty sharp already). But notably was able to make the s30v hair shaving sharp easily, something I've had trouble with. Inexpensive and useful, I love this stone. It's not the Ninja sharp 8000+ grits that you can find, but for pocket knives and EDC, it's perfect and inexpensive. Get One!!!!!!!!!!!!
As Mal Knives shows in a review, the Chef's Choice sharpener creates a triple bevel on the blade, which allows it to work with both Asian and European/American knives. The bevels are at roughly 25 degrees, 20 degrees, and 15 degrees. This triple bevel design increases the length of time required between sharpenings. However, one Amazon customer reviewer disliked the sharpening results on Asian knives with this machine.

If style and interior décor are important to you and you intend to leave your sharpener on the countertop, you will be happy to hear that this Chef’s Choice is available in six stunning colors. The colors include black, white, red, chrome, brushed metal, and platinum. Though they may not be the best matches for many country or vintage-style homes, these sharpeners will look fantastic on the countertop in an urban, industrial, or modern-style home.
This was the first Whetstone that I've ever purchased. After reviewing several 'how-to' videos, I jumped right in to use it. I found the process nearly meditative and the BearMoo stone extremely effective! The first knife I sharpened was very dull with small, jagged edges. The 1000 grit side effectively removed the jagged indentations and created a nice cutting edge. The 4000 grit side made the knife razor sharp. The process took nearly 40-minutes.
I really like this stone. The 1000/4000 grit combination is perfect for my needs. I'm a woodturner, and belong to a club that brings in professional turners from around the world. One had an eye opening test of sharpness. He stacked around 25 new razor blades in a box with one open side. The box assured that the blades were in perfect alignment. If you looked at the blades' sharp ends head on, all you saw was black. His point was that if you can see the edge, the blade is not sharp. Any reflection from the edge, again, facing it head on, is a dull spot. My long story leads to the fact that I was able to sharpen several knives to the point of not seeing the edge. This is not the stone to use if you are trying to remove nicks from a blade. A lower grit will do that job. This is for putting a fine, "invisible" edge on the blade, and with the right technique, that's what it will do. Another thing to consider is the fact that these stones are "sacrificial" A stone wears because it is deliberately giving up dull surface particles to expose the sharp ones below them. Anyone expecting a stone to last forever is mistaken. Bottom line? I think this is a great stone that takes my knives to the level of sharpness I need in both woodworking and cooking. I also like the rubber frame it sits in, giving you much better control over the stone. Your efforts can go into sharpening without having to steady the stone on your workbench or countertop.

The smaller the angle between the blade and stone, the sharper the knife will be, but the less side force is needed to bend the edge over or chip it off. The angle between the blade and the stone is the edge angle – the angle from the vertical to one of the knife edges, and equals the angle at which the blade is held. The total angle from one side to the other is called the included angle – on a symmetric double-ground edge (a wedge shape), the angle from one edge to the other is thus twice the edge angle. Typical edge angles are about 20° (making the included angle 40° on a double-ground edge).[1] The edge angle for very sharp knives can be as little as 10 degrees (for a 20° included angle). Knives that require a tough edge (such as those that chop) may sharpen at 25° or more.
Trying to decide which type of knife sharpener will work best for you in the battle of manual vs electric knife sharpener? It’s not an easy battle, since there are so many different types, methods, versions, brands bombarding you with options. One thing is for sure though, using sharp knives in the kitchen is imperative. Continuing to use dull blades when cutting and chopping can cause more than just frustration, it can cause injury. Thus, it’s important to figure this out. Just what type of knife sharpener should you buy? The question usually comes down to manual vs electric knife sharpener.

If you want to start hand-sharpening knives, and you’ve never used stones, this kit has everything you need. It includes a medium-grit stone for sharpening and an Arkansas stone for finishing. It also includes a honing solution that protects and cleans the stone’s surface as well as a small plastic guide to help sharpening novices learn the correct angle for sharpening. This is the classic method for sharpening knives, which takes some time to master, but once you learn how to use a stone, you can sharpen knives to any angle you prefer.
Oilstones, like the Norton whetstone, can be made out of natural or synthetic material like Novaculite, Aluminium Oxide, or Silicon Carbide. As per the name, oilstones require the use of oil as you sharpen your knife's blade. This type of stone is slower at sharpening or honing a blade and it can be messy and you need to always have some oil on hand but it creates a nice sharp edge and a beautiful polish.
My first set of sharpening stones so I have nothing to compare them to. For $50, though, great price to get into the world of sharpening. Stones are great and easy to use. Was able to put hair shaving edges on knives. Took a couple of knives to feel comfortable and better with the process and how to sharpen, but the stones you get work great. Here's the secret though. Get the green leather stoping block as well. As great as the stone are, I have found that stroping the knife after the fact is what really brings out that razor edge. And after using the knife, stroping it again, will restore and keep it razor sharp. Hope you enjoy it as much as I am.
The toughest angle to master is the angle at which you'll sharpen the edge of the knife. For a Japanese knife, that should be around 12-15 degrees. Before you reach for the protractor, a good test is to get roughly half an index finger's gap between the spine of the knife and the stone (see above). Remember to remove your finger before you start sharpening. For a Western-style knife, you want an angle of about 20°, so raise it ever-so-slightly higher.
A major benefit of sharpening your knives on a sharpening stone is that you can thin out your knife. When thinning out a knife, you grind away extra material on the sides of the blade, making the blade thinner. Thinning of a knife is useful for knives that are often sharpened, as the cutting edge gets fatter when the blade is sharpened more often. Thinning is of great importance for the preservation of good cutting properties.
This is a great sharpener for budget conscious cooks. You can use it with equal facility whether you’re right or left handed, it has a convenient finger guard to cut down on accidents and most important, it only takes a few swipes on a regular basis to keep your knives in tip-top condition. It’s not glamorous. It won’t add anything substantive to your kitchen decor. But it will ensure your knives are always ready for whatever dish you have in mind.
Whetstone has two different sides of grain for sharpening and polishing knife edges. These softer Japanese stones have several advantages over harder stones. Because they are softer, they do not become glazed or loaded with detritus. Plus, they are lubricated effectively with water rather than oil, but can be used with either. Submerge the stone in water for about 5 - 10 minutes. Continue to apply water while sharpening with the Whetstone Cutlery Two sided Whetstone Sharpening Stone. The stone releases small particles during the sharpening process; this powder in combination with water allows the sharpening. After a while you will notice a small burr at the edge. Now repeat the same process on the other side of the blade. Finally, turn the stone over and repeat the procedure, this time using the finer grit of the stone. In order to remove the remaining burr, pull the blade at an angle over the stone. Rinse the stone and clean off the grinding residue. Clean your knife with hot water.
Before I even begin discussing much else about this sharpener I would like to take a moment to discuss its four sharpening slots. Upon reading consumer reviews, I found that many people were confused by the fact that there were four slots and mistakenly believed that this was a four stage sharpener. This is a two stage sharpener. It has one stage with a rough grit and one stage with a fine grit so that you can adjust the type of sharpening to the dullness of the blade.
Both Belgian Blue and Vielsalm Coticule are ancient stone layers found in the Belgian Ardenne Mountains with characteristics similar to both Novaculite and Siliciclastic sedimentary stone in that it is a metamorphic stone consisting of both gray and yellow volcanic ash mixed with tiny Spessartite Garnet crystals suspended in a clay matrix. However, due to its geology, both types of stone occur only in vertical seams sandwiched between two thick layers of bluish-purple slate and thus, they must be meticulously extracted mostly by hand. However, this type of extraction process is both very time-consuming and very labor-intensive and, quarrymen can only extract the stone for a few months each year due to inclement weather conditions. Consequently, both Belgium Blue and Coticule whetstones tend to be somewhat expensive.