Natural Japanese waterstones are still available, though nearly all quarries are closed. However, there still exists a large quantity of mined stone. Quarries containing the finest stones have all but been exhausted. If one were to be found, it would cost a fortune. Even so, similar, less than perfect stones that are currently produced can still fetch well in excess of €400!

Whetstones may be natural or artificial stones. Artificial stones usually come in the form of a bonded abrasive composed of a ceramic such as silicon carbide (carborundum) or of aluminium oxide (corundum). Bonded abrasives provide a faster cutting action than natural stones. They are commonly available as a double-sided block with a coarse grit on one side and a fine grit on the other enabling one stone to satisfy the basic requirements of sharpening. Some shapes are designed for specific purposes such as sharpening scythes, drills or serrations.[9]

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.

The goal when sharpening is to create a burr, which is a tiny whisper of metal left on one side of the blade. You'll know you have a burr when you can feel one smooth and one scratchy side to the edge. Warner's is formed in no time at all; I struggled. Nevertheless, eventually I got there. Once you've got the burr, it's time to move on to step three.
Shapton Glass 320, 500, 1,000, 2,000 and 16,000. I have the 4,000, and 8,000, they are absolutely fine, great in fact but I just don’t use them as much as the others. These stones excel on knives made of hard steel, the hardest steel is no match for these. This does not mean you can’t sharpen hard knives on the Naniwa brand of course, you can. I have been using this particular brand of stone for many years and I absolutely love them.
Sharpen your dulling knives and other tools quickly and easily with a choice from the best knife sharpener selection at Academy Sports + Outdoors. The handheld knife sharpeners feature large, ergonomic handles that generally fit either hand safely and securely, and finger guards that are full length to protect your fingers. The sharpening blades are often made of diamond-honed tungsten carbide for quick restoration of extremely dull blades or ceramic rods for a polished finish. A handheld knife sharpener tends to be small and portable, perfect for use out in the field when you need a professional knife sharpener to sharpen your hunting or fishing blades.
Medium grit stone works as well as some of the more expensive ones. Perhaps it doesn't cut as fast as a shapton or norton, but it builds up a nice mud leaves a pretty refined edge. Of course you could improve with a 4k-6k stone, but many would be happy with the edge this 1k leaves. I sharpened 3 knives in my set in about an hour. My slicer needed quite a bit of metal removed to fix some edge chipping and this stone did the job, although it took 15-20 minutes of work.
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.

From the moment I ordered the knife set, I was emailed every step of the way till they were delivered. When I opened the box I instantly knew I made the correct decision. The weight, balance and edge were perfect. A few of my friends have handled them as well and all have asked the same question. How can I get these. I highly recommend these knives.