Obsidian is volcanic glass, which is considered to be a supercooled liquid (glass in fact flows, albeit very slowly).
(Obsidian; is; volcanic glass, which is considered to be a supercooled liquid () (volcanic glass; to be; a supercooled liquid (glass in fact flows, albeit very slowly)) (a supercooled liquid; flows albeit very slowly; )
Obsidian volcanic glass a supercooled liquid
is to be flows albeit very slowly
volcanic glass, which is considered to be a supercooled liquid (
a supercooled liquid (glass in fact flows, albeit very slowly)