Hardness Comparison: Kitchen Knife vs Granite Counter Top

AlephZero · **on:** April 26, 2018, 05:30:26 PM

I was just watching a Youtube video and someone in the comments expressed their worry about damaging the counter top, which seemed to be granite..

Now, I know granite is smurfing hard stone (some source said 7 on Mohs scale) and kitchen knives are not usually made out of supersteels (again same source stated comparative hardness of 5 - 8.5)...

So, as the title says: Anyone know which one is harder and will actually damage the other?

Don Pablo · **Reply #1 on:** April 26, 2018, 06:00:09 PM

I guess both will damage each other.
Should be using a nice wooden chopping board!

AlephZero · **Reply #2 on:** April 26, 2018, 06:09:48 PM

I do, but then again, I don't have granite counter top either

Don Pablo · **Reply #3 on:** April 26, 2018, 06:17:42 PM

Same here.

Was talking in reference to the youtube video you mentioned.

AlephZero · **Reply #4 on:** April 26, 2018, 06:24:22 PM

I know

Vidar · **Reply #5 on:** April 26, 2018, 06:57:06 PM

I do have a kitchen knife and a granite slab, but I'm not sure if I'm curious enough to damage either.. I could use a cheap knife but that would kind of invalidate the test anyway.

ThePeacent · **Reply #6 on:** April 27, 2018, 11:49:02 AM

granite will be fractured and small dings will fly out if a steel blade hits it with enough force,

in return the steel will roll and most likely present micro-chips and scratches from the quartz (hardness 8 ) in it, while just displacing or crushing the mica and feldspar particles in the granite (hardness 2.5 and 6 respectively) as the the steel (ca. 6.5 hardness) blade moves

if the contact is light and minimal rolled edge is the most common result, the very apex would deform sideways depending on the angle of impact