There is an issue with the numbers from this aspect.
https://i.imgur.com/thcEvfl.png
OK, but then why?
https://i.imgur.com/4IrpmpH.png
And no it is not a display bug I checked it is taking 44 spirit per cast of boulder. Plus I have some resource reduction affix. So you may want to check if that is being applied properly to this.
Also when the Aspect makes Boulder a Core skill, why does it lose it’s Wrath tag? As if this class needs to be made any weaker. Even the Sorc Mastery skills retain both tags. Why is there no consistency?