we feel the dirt on it could be somebody's ashes.

It is dirt. Basically, it's cosmic crud.

It's literally dirt. It's basically cosmic grime.

Alec looked at her and shook his head. "How do you manage never to get mud on your clothes?"
Isabelle shrugged philosophically. "I'm pure at heart. It repels the dirt.

Time is either gold or dirt. It is dirt to the lazy, and gold to the diligent.

This is just the dirt that was here.