It is better to understand the difference in sharpening stone materials before you are going to make any decision. Among the available options in the market today, Waterstone, oilstone and diamond stone are the most common type of sharpening stone. Each of stones comes with advantages and disadvantages. Waterstone and oilstone are available in natural and synthetic models. Synthetic are the most common and easy to find as man makes them. As the use of natural stones (e.g. original Arkansas or Japanese natural whetstones) is has diminished in popularity, they are beginning to rare in the market. Artificial stones have a more consistent particle size and controlled with a tight mechanism in providing high-quality sharpening stone.
In addition, there are three broad grades of Japanese Water Stones consisting of the Ara-to (rough stone), the Naka-to (middle/medium stone) and, the Shiage-to (finishing stone). However, it should be noted that the various grades of natural Japanese Water Stones vary widely in both density and grit size from stone to stone and thus, they do not translate well to American or European abrasive standards. Furthermore, because they are significantly softer than Novaculite, Japanese Water Stones must be flattened more often and do not last as long as a either Novaculite or Coticule stones. But, because they form a slurry of fine particles when used, they also do a superior job of both cutting and polishing.
Meanwhile, if you want something that you can use to sharpen a variety of knives and edges, including small and pointed tools, you might want to consider the DMT WM8CX-WB 8-Inch Duo Sharp Plus Bench Stone – Coarse/Extra Coarse with Base. For less than a hundred bucks, you can even use it to repair a damaged edge because of its extra-coarse diamonds.
Let’s start with Arkansas. If you have heard about Arkansas oilstone, it uses the Novaculite stone that mined in Arkansas. The most expensive of Arkansas stone is the Hard Translucent model that begins to rare in the market. If you want to shop for Arkansas, they are available in different grade starting from Soft Arkansas, Hard Arkansas, Hard Black Arkansas and Hard Translucent Arkansas. The finest grade of Arkansas can shape such of mirror polishing edges.