How durable is human skull ?

When I was about 10 years old ,I fell upside down(landed on my head) from a tree(From above 3-4 meters ) on a floor (made of Brick and cements ) and was completely fine except that it hurt like hell .I was surprised that my skull didn't crush or at least I didn't bleed .

So How durable is a human skull ?I guess around 9-B ?

 

[CIC_SHARK]

6-A

 

[Abstractly_a_Protagonist]

Did the cement and the brick break on the impact?

 

[KLOL506]

Durable enough to survive punches from MMA fighters and full-powered curbstomps.

But nowhere near 9-B. 9-C rifle rounds and shotgun slugs can smash it like an egg-skull.

 

[Nierre]

Ouch...

 

[Diablo_]

Did the cement and the brick break on the impact?

No both my head and the floor was fine which was surprising to me .

 

[Abstractly_a_Protagonist]

No both my head and the floor was fine which was surprising to me .

Not wall level then.

 

[H3110l12345I20]

It usually breaks at around 14.1 to 68.5 J, though if you know any pressure points or hit someone in the face hard enough, you can easily knock someone out without the assistance of the floor's impact.