Blender rotate rock around axis Animation Blend Space


I hope I am on the right place to ask this.
After my earth elemental was modelt I animated it also in Blender so far so good.
When I now import my model and try to set up an 1D blend space I recognize
a strange animation effect. After researching I found out it is connected with the rotation of some bones.
(tried to animate rocks that rotate around its axis).

Now when the blend space is trying to translate between those two animations it gets confused/distorted by the rotation axis,.

My question is it possible to make a rock rotating around its axis and loop this. (Idle animation)

Thx for help, and sorry for the bad english.

(Each “rock” should rotate around its axis)

Take a look at this tutorial. It will show you one way to rotate an item.