Geo 365: June 2, Day 153: Pumice?

The interpretive signs here describe this component of the flow as "pumice," a usage I'm not terribly comfortable with. It's obviously highly vesicular, but its density is nowhere near as low as what is traditionally called pumice- I very much doubt it would float on water, in the case of most pieces. I would be happier describing this with the adjective "pumiceous," meaning pumice-like. On yet still another hand, though, the general public, for whom these signs are intended, would either read the two words as synonymous, be confused by the distinction, or throw their hands up in exasperation: "Oh, those scientists and their terminology!"

I'm inclined to let this bit of subtle pedantry slide.

Photo unmodified. August 21, 2011. FlashEarth location.