In Search Of The Best Diamond Sharpening Stone 
For those in the know, diamond sharpening stones are the only choice when it comes to sharpening their tools. Talk to any one who is serious about sharpening, and you will find that oil and water stones just don’t make the grade when compared to diamond sharpeners.
Diamond sharpening stones last longer, cut fast and importantly stay dead flat during their entire lifespan of use. What’s more, they are much cleaner and more convenient to use.
While traditionally they were more expensive to buy, these days it is quite possible to purchase a high quality diamond stone without breaking the bank.
So which is the best diamond sharpening stone you can buy in 2018? Well in our top 5 review round up, we answer that and a whole lot more. Below you will find our top 5 picks at a glance. For in depth reviews of each, please read on.
Top 5 Best Diamond Sharpening Stones
1. DMT WM8EF-WB 8-Inch DuoSharp Plus Bench Stone Extra Fine
2. Smith's 50008 8-Inch Diamond Tri-Hone Bench Stone
3. EZE-LAP 62F 2 by 6 Fine Diamond Stone with Walnut Pedestal
4. Atoma Diamond Sharpener Medium - #400
5. DMT W250CXNB 10-Inch DuoSharp Bench Stone Coarse
Why Choose a Diamond Sharpening Stone?
One of the most common reasons for using diamond sharpening plates is that they are flat and do not become hollowed out after frequent use.
The flatter the sharpening the stone the more effective it is to use. In fact, they are so effective, some extra-coarse diamond stones are sometimes used to flatten oil or water stones.
The only real disadvantage of using a diamond stone is the fact they are more expensive to buy.
However, when looking to buy a diamond sharpening stone, you should remember that this is a tool that will last a long time. The initial cost is therefore very often worthwhile as you can save money in the long run.
The Different Types of Diamond Sharpening Stone
Diamond sharpening stones are made by attaching small diamonds to the face of a metal plate.
These small industrial diamonds provide a much harder surface than what is possible with any other type of sharpening stone.
However, there are varying degrees of quality in the manufacturing process, and not all diamonds perform the same function.
It is important to know the difference when buying a diamond sharpening stone.
Non-Continuous Diamond Surface
This is the most common style of diamond stone. A non-continuous diamond surface contains tiny holes that are able to capture the swarf. These stones cut very fast and are very simple to use, (hence the popularity).
Continuous Diamond Surface
These are the preferred stones when sharpening tools with points that could get caught in the recesses of the non-continuous diamond surface.
Both types of diamond stones are available in mono-crystalline and poly-crystalline diamonds. The mono-crystalline diamonds are what you should opt for if you can as they are more durable and will last longer.
Best diamond Sharpening Stone – 2018 Update
The multi-patented DMT 8 inch DuoSharp Bench Stone takes the number one spot in our 2018 best diamond sharpening stone review update, because it balances excellent value with high quality manufacturing processes.
The DuoSharp is a precision flat, large 3″ x 8″ double-sided diamond sharpener (one side is fine 600-grit for all around sharpening, the other is extra fine 1200-grit for getting your blades to a razor sharp edge).
The sharpening process is incredibly fast with this tool. Where a dull knife may take 50 strokes on a conventional whetstone, you could find yourself achieving the same results with the DuoSharp in just ten strokes. (Not only does this save you time, it is also easier to maintain a consistent blade angle when using fewer strokes.)
The DuoSharpe is very sturdy to use too, which also increases its effectiveness. The robust plastic base holds fast utilising its wide feet – this tool can be used without sliding across your workspace.
The stone snaps into the base very snugly with no irritating ‘play’ to speak of. For added security, you can eve fasten the base to a workbench or other large surface.
Sharpening is clean and efficient. As with all diamond sharpening stones, there is no need for any messy oils or water.
The not so good bits
As with all manual stone sharpening, the sharpening process does take a little getting used to. Where the DuoSharp falls short is that the instructions supplied are a little scant in detail, (however, the DMT website offers lots of guidance as well as handy how to videos).
Another small issue is the fact the 600 grit side is actually a little rough on first use. While it sharpens extremely quickly, finer edged knives should be sharpened with extra care until the plate has had time to be worn in. Overall these are minor niggles however.
The DMT WM8EF-WB 8-Inch DuoSharp, provides extremely fast sharpening results. If this is your first foray into the world of diamond stone sharpening prepare for a shock. You won’t look back.
In our opinion, the DMT DuoSharp is the best diamond stone sharpener for the money in 2018.
Smith’s 50008 8-Inch Diamond Tri-Hone Bench Stone
The Smith’s (#50008) 8″ Diamond Tri-Hone Bench Stone is a very much, ‘anything you can do, we can do better’ approach to our top pick DMT.
For just a little more initial investment, you are getting two interrupted Surface Diamond sharpening stones, with a third thrown in: a soft natural Arkansas stone; which are highly regarded for finishing.
This kit amounts to a one coarse diamond stone (325 grit), a fine diamond stone (750 grit), and the Natural Arkansas stone (~1,000 to 1,200 grit). A superb all round sharpening solution.
The 2 diamond stones feature a unique overlapping, oval-hole design. As we mentioned in our look at the different types of diamond sharpening stone above; the popular non-continuous diamond surface design, helps speed up the sharpening process by collecting and holding the metal filings that ordinarily build up during sharpening.
A great little feature with the Smith’s (#50008) 8” Diamond Tri-Hone are the Micro-Tool sharpening pads that are in place on the end of each of the diamond plates. These are perfect for sharpening small cutting edges and tools, or the tip of your knife blade.
The Bits We Love
The Smith’s Tri-Hone excels at sharpening medium to large-sized knife blades. Single or double bevel blades can be easily accommodated with this tool.
Woodworking tools, fixed-blade broadheads, or straight razors can also be sharpened with these stones.
The three 8″ x 2-1/2″ stones are color-coded and labeled for easy stone identification meaning even the most novice user should be able to run with this in a short time without any stress. A detailed sharpening angling guide is also provided.
As you can see from the images, the plates are mounted on a durable triangular-shaped stone holder. Handles on each end facilitate easy rotation from one stone to the next.
The sturdy, non-skid base holds the sharpener in place surprisingly well, (not that you need to exert too much effort in your blade passes with this anyway).
The design incorporates a tidy little trough in the bottom of the base to catch any oil drippings from the Arkansas stone finishing process.
A 1 ounce bottle of Smith’s Premium Honing Solution is provided.
The not so good bits
So with all these positive points, why did the Smith’s Tri-Hone not receive our coveted top spot?
The main reason is that with a list price is higher than some of the other stones reviewed here, this doesn’t quite offer the same value for money as the DMT. Slight design choices in the size of the diamond stone mounts, make this a little difficult to use with pocket-knives too.
Overall, the complaints are just minor issues. If you are in the market for spending a little more money, the fact the Smith’s 50008 8-Inch Diamond Tri-Hone contains 3 excellent graded stones to complete your sharpening needs makes this a worthwhile choice.
A high quality, high performance diamond sharpening solution.
EZE-LAP 62F – 6″ Fine Diamond Stone with Walnut Pedestal
The Eze-Lap Fine Diamond Stone Sharpener is a bit of outsider in our top 5 list as it comes from one of the lesser known companies showcased here.
However, you shouldn’t let that put you off. Their 6 inch fine diamond (600 grit) is one of the best small diamond stones you can buy for the money.
This durable 2-Inch by 6-Inch stone is mounted on a rather pleasing looking walnut pedestal.
There’s some impressive design work gone into this too. Although you may not have heard of them, EZE-LAP Diamond Products have actually been around since the early seventies.
The company has an impressive amount of patents under their belt, one of which is to do with the process they use to bond the industrial diamonds to the plate that becomes your sharpening stone.
There’s no denying that their sharpening stones are extremely hard and durable considering the price you are paying.
The company states that carbide, tool steel, titanium, ceramics and some of the newer synthetic materials being used by knife manufacturers today can be sharpened using their tools.
And while we were not in a position to test all those materials on the Eze-Lap 6 inch diamond sharpener, the results that we did see using this tool certainly did impress.
The 600 grit is a good choice medium grade that works for sharpening and fine honing, (compared to the DMT and the Smith’s you are only getting one stone here after all).
Furthermore, the aforementioned walnut base allows for a really good grip. It’s just the right size to grab a hold of, and secures the actual diamond stone with no problems at all.
Being a diamond stone there’s none of that messy oil or water to deal with, and to top it all off, the tool is completely designed and manufactured in the USA.
An excellent tool for the money. You are getting a quality diamond stone that is easy to use and looks good too.
Sure, you’re not getting the versatility of more than one stone with this solution, however for some just the one stone will definitely be enough. The 600 grit will see to most sharpening needs. Another worthy addition to our top 5 best diamond sharpener review roundup.
Atoma Diamond Sharpener Medium – #400 Grit
The Atoma Diamond Sharpener is a medium to rough 400 grit diamond stone that is extremely effective when used properly.
It actually makes our list as it is one of the best methods of flattening your Japanese waterstones. As a lapping plate, the Atoma is very good value for money. The surface is designed not to clog, and rinses clean very easily. It is a lot less expensive than other flattening stones you can buy.
However, the trade off with this highly abrasive diamond stone is that it is not necessarily recommended for novice users. You could end up damaging your knives using a stone such as this if you don’t know what you are doing.
Atoma use heat-binding to adhere the diamonds to the surface of the stone. As you would expect, the finished result is an extremely durable sharpener, (the complete plate measures 8.25″ x 3″ x 0.5″H ).
A very hard-wearing diamond stone sharpener that works very well as a lapping plate to flatten your waterstones. Can still be used to sharpen your tools of course, however you need to be confident in your sharpening skills as the coarseness of the Atoma diamond sharpener could wreck your knives if not used properly.
DMT W250CXNB 10-Inch DuoSharp Bench Stone Coarse / Extra-Coarse
DMT make our list a second time. Their 10-Inch DuoSharp Bench Stone Coarse / Extra-Coarse diamond sharpening stone is another excellent tool from this USA based company.
Again the patented Precision flat manufacturing process has been used to build a double-sided sharpener, with both coarse and extra-coarse diamond surfaces.
The coarse diamond stone comes in with a 45 micron / 325 mesh and can be used to quickly and easily restore a neglected edge.
The extra-coarse diamond stone is 60 micron / 220 mesh, making it ideal for edges that are significantly damaged.
The extra-large diamond surface gives the DuoSharp Bench Stone the ability to sharpen virtually any knife or edged tool. The list is long on what this sharpener can handle: large tools such as axes, hatchets, machetes, lawn and garden tools can be sharpened using this beast.
When sharpening tools such as these however, you need to ensure that your diamond stone is firmly fixed in place. Thankfully, the non-skid rubber mat helps keep the DuoSharp stuck fast during even the most aggressive sharpening.
Again no messy oils are required when using this tool. The innovative diamond surface allows you to easily sharpen dry or with water.
The 10-Inch DuoSharp Bench Stone measures 10 x 4 x 0.38 inches (LxWxH), and it weighs just 1.5 pounds.
A fantastic easy to use tool that comes highly recommended. If you decide not to opt for our top pick DMT due to the grade of the stones, (i.e you require something with courser grit) or you need something a little larger in size, then this is definitely worth your consideration instead.
Another high quality diamond stone sharpener with from one of the best diamond stone brands around today.
About Diamond Machining Technology (DMT)
As DMT made it on to our top 5 best diamond sharpeners list twice, we thought it would be a good idea to take a closer look at the company.
Diamond Machining Technology (DMT) are an American company that first came to be back in 1976.
Based out of Marlborough, Massachusetts, DMT have invested heavily into sharpening R&D over the years, with a number of patents attached to the company in the design and manufacturing process.
Not one to rest on its laurels, DMT continues to develop new and exciting diamond sharpening solutions for both consumer and commercial applications to this day.
The DuoSharp bench stone (as reviewed above) is a very popular product line, however other innovations from DMT include their patented Diamond Whetstone, and the Diafold Magna-Guide Sharpening System.
DMT also guarantee that all of their products be free of defects. In fact you can be confident that if you purchase any product that doesn’t live up to DMT’s high standards the company will replace it free of charge.
Last Updated on 22nd May 2019