It is almost tumbled, so edges are broken down.
In the ancient ag
thread , the
natives here always plant in sand.
Seems it works as a canteen. The aerial photos plainly show they avoided the dirt overburden, and planted in drift and washes.
So, seems like a good thing to mix into buried wood to keep water pockets and air spaces.
Don't think i would use it on surface, standard rocks would work better as they can grow lichen, and break down.
But the glass buried would work fab, and would prob be good as a wick pocket/channel to suck moisture down deep to
root area.