Skip to content

Rob Cosman's Diamond Stone: Standard

Save 18% Save 18%
Original price $163.00
Original price $163.00 - Original price $163.00
Original price $163.00
Current price $133.00
$133.00 - $133.00
Current price $133.00
in stock, ready to be shipped
Full Description
Customer Reviews

Our 300 / 1000 grit, double-sided, Standard Diamond Stone is a great sharpening stone for general use around the shop.  We do NOT recommend using our Standard Diamond Stone as part of your premium chisel or hand plane blade sharpening system (instead use our Premium Diamond Stone for such applications).  Our Standard Diamond Stone is great for sharpening pocket knives, axe blades, drill bits, and most other edge tools found in the shop.

Our diamond stones use only high-quality mono-crystalline, man-made, industrial diamonds permanently adhered by electroplating to a thick, precision milled, steel substrate.  Use the 300 side for coarse sharpening needs and the 1000 side for your medium sharpening needs.

We quality control test EVERY diamond stone we receive to determine if it's flatness is within our standard of being absolutely flat.  Diamond stones that test between .0016 and .004 (1.6 to 4 thousandths of an inch) out of perfectly flat, are graded as "Standard Diamond Stones."  Diamond stones that test between .0000 to .0015 (perfectly flat to 1.5 thousandths of an inch) out of perfectly flat are graded as "Premium Diamond Stones."  

Premium diamond stones are recommended for use in sharpening premium chisels and hand plane blades where near perfect flatness is a must.  Standard diamond stones are recommended for all other edge sharpening needs.

Product details 

  • Precision milled, double-sided diamond stone 3" wide x 8" long.

  • Electroplated with Monocrystalline industrial diamonds.
  • Fine 1000 grit (5 micron) on one side and coarse 300 grit (50 micron) on the other.

  • Clearance channels on the coarse side produces a faster, cleaner cut.

  • Guaranteed flat to within .0016 and .004 (1.6 to 4 thousandths of an inch) of being perfectly flat.

  • Recommended for general sharpening of edge tools around the shop. 
  • Not recommended for as part of your premium chisel or hand plane blade sharpening system (instead use our Premium Diamond Stone for such applications)
  • Comes complete with a non-slip mat.  

One-Time Break-in Procedure: The 300 grit side of our diamond stones requires a one time break-in procedure.  There is an excess layer of diamonds which needs to be removed before the surface is at its optimum. Break-in the stone by rubbing a piece of steel (a screw driver shaft, plane blade, etc.) over the entire surface of the 300 grit side for 1 minute.  Rinse and wipe off the diamond stone; it is now ready to use. Failure to break-in the 300-grit side can lead to cross-contamination of water stones. 

Customer Reviews

Based on 12 reviews
Sharpening System

Wonderful shopping experience.
I was even contacted by Rob to insure my order was what i expected. Everything arrived and worked together for my needs. Great sharpening arrangement.


Bill Van Dusen
It’s good

It works fine for me. I’m not disappointed.

Jag Mollerup
Great Products and Service

The stone is really high quality and Rob provided excellent service, even calling me to be sure I was happy with the purchase. This is next level service and i will be buying from his site again!

David Penton
Diamond Stone Review

Excellent tool. I mostly use it to flatten my Shapton stones. It is an affordable option for that, considerably less expensive than many lapping tools.

Hart Wichern
Diamond sharpening plate

This is my second one!
Excellent …..
The fact that I can flatten my other stones is a lovely bonus!
Great product! Thanks for making it available!