It's a basaltic rock (a rock similar to rocks that form from lava in places like Hawaii, and the crust of the ocean), and such rocks can only form on certain planetary bodies that are large enough to differentiate (an iron core, a silicate mantle, etc.).
(It; 's; a basaltic rock (a rock similar to rocks that form from lava in places like Hawaii, and the crust of the ocean) (rocks; form; from lava) (such rocks; can only form; on certain planetary bodies) (certain planetary bodies; are; large enough to differentiate)
It rocks such rocks certain planetary bodies
's form can only form are
a basaltic rock (a rock similar to rocks that form from lava in places like Hawaii, and the crust of the ocean
from lava
on certain planetary bodies
large enough to differentiate