Weapon Skill Icons

[Haldarn]

The color of the icons is the element of the WS, not the skillchain properties. Earth crusher is yellow and deals earth damage, etc. pretty straightforward to me.

Yes but Skullbreaker is Red and doesn't deal Fire damage.
Piercing Arrow is Green and doesn't deal Wind damage.
The Great Axe weapon skills deal various different elemental damages, but are all Grey.

There are plenty of other examples.