Diamond vs. Silicon Carbide Sandpaper: Which is Best for Sanding Ceramics?
We’re often asked about the difference between diamond sandpaper and the more common silicon carbide sandpaper.
The truth is that there are significant differences in hardness, durability, real cost,and also in the quality of the finished surface.
Let’s break down each aspect then.
Hardness
Hardness is usually measured using the Mohs scale. On this scale, diamond ranks 10/10, while silicon carbide is around 9/10, making it slightly softer.
Grain Structure
Diamond sandpaper grains are usually tiny cube-shaped particles that fracture slowly over time, creating new sharp edges as they wear. This breakage is more gradual than silicon carbide, which tends to fracture into needle‑like shapes and wears down faster.
Diamond grains are typically bonded with resin to a metal or similar backing, although other bonding methods exist.
Silicon carbide is usually bonded with glue or resin to paper or cloth. This makes it less durable.
Lifespan and Cost per Use
Diamond sandpaper is more expensive per sheet, but one diamond sanding block can replace 100 to 200 sheets of silicon carbide sandpaper. Over time this makes diamond the more cost‑effective choice. Especially when working with abrasive materials like stoneware, porcelain, or clay with high grog content.
In addition, fewer sanding sheet changes mean less downtime and increased productivity.
For sanding hard tiles, porcelain, or industrial glass‑ceramics, diamond sandpaper is highly recommended.
Surface Quality and Finish
Clay tends to clog silicon carbide sandpaper, reducing its performance quickly. Diamond sandpaper clogs much less than the silicon carbide.
For polished finishes, where surface quality is a priority, diamond provides a more consistent result with fewer deep scratches.
Some makers use silicon carbide for rough sanding (as it is cheaper) and then they finish with fine‑grit diamond sandpaper (for example, 200 grit) for a perfect final touch.
Material Suitability
For softer ceramics, silicon carbide works well and is a cost‑effective option. It is also used to remove porosity and prepare pieces for glazing.
Wet Sanding: Yes or No?
We recommend wet sanding for both diamond and silicon carbide sandpapers. Because water extends the life of the abrasive, produces a more even sanding action, and in many cases, reduces dust in the air.
Grit Equivalency
Grit ratings between diamond and silicon carbide are not perfectly equivalent.
For example, a 240 grit silicon carbide would be roughly similar to a 200 grit diamond, although diamond will generally leave a cleaner surface.
---------
If you’d like to explore our diamond sanding solutions for ceramics, you can check them out here:
