This stone light as a breath

This stone, light as a breath,

full of tiny, air-blown caves.

It weighs next to nothing,

like a promise that misbehaves.

The surface, rough and gritty,

a dark grit that comes away,

sticks to my finger tips,

making a mess of the day.

I turn it in my hand,

this thing of cooled-down fire,

a sponge of solid rock,

holding nothing but desire

for form. It's so porous,

you could almost pour

water through it. What does it hold?

Or has it lost so much, it can't hold anymore?