That’s a neat idea—rocks do have their own subtle hums from crystal lattices and pressure waves, almost like a quiet choir. I could see a guitarist tapping a quartz crystal, letting its resonance echo a message about protecting the Earth. My favorite rock to tell a story? Obsidian from the volcanic vents of Hawaii; it’s a volcanic glass that captures the history of eruptions in its smooth, dark flow. It reminds me that even the most fragile things can hold a powerful tale.