How to use "chipping" in a sentence

7.0 pm I've been chipping at the rock for almost three and a half hours

12.00 am My headlamp is on and I'm chipping at the boulder

Now that I've stopped chipping I feel cold

I start chipping at the boulder just to keep warm.

I spend most of the day chipping, resting, and counting the minutes before my next drink of water.

Then, shaking hard, I continue chipping at the boulder