Previously I was unable to find any videos showing off all the sounds and properties of the materials listed on the Valve Developer Wiki, so i decided to make a video of them myself.
I hope this helps you.

0:00 Notice

===Special===
0:32 default
0:55 default_silent
1:14 floatingstandable
1:35 item
1:55 nodecal
2:15 player
2:55 player_control_clip

===Concrete / Rock===
3:20 boulder
3:46 brick
4:10 concrete
4:30 concrete_block
4:50 rock

===Metal===
5:10 canister
5:37 chain
6:03 chainlink
6:25 crowbar
6:45 grenade
7:13 gunship
7:40 metal
8:03 combine_metal
8:26 metal_barrel
8:50 floating_metal_barrel
9:09 metal_bouncy
9:58 Metal_box
10:19 metalgrate
10:42 metalpanel
11:01 metalvent
11:23 metalvehicle
11:45 metal_seafloorcar
12:13 slipperymetal
12:39 solidmetal
13:02 paintcan
13:31 popcan
13:49 roller
14:06 strider
14:41 weapon

===Wood===
15:05 wood
15:39 wood_Box
16:04 wood_Furniture
16:24 wood_Panel
16:47 wood_Plank
17:07 wood_Solid

===Terrain===
17:31 dirt
17:59 grass
18:20 gravel
18:43 mud
19:06 sand
19:24…