Why is it being called a Rock here?
"The large variations on the light curves indicate that ʻOumuamua may be either a highly elongated object, comparable to or greater than the most elongated Solar System objects, or an extremely flat object, a pancake or oblate sphereoid."
So its either a elongated oblate sphereoid or a Flat Pancake like Disc in shape.
Light curve observations say its mostly Metal right? A clump of metal, might be more fitting.
Necro-bump this 2020: http://gamrconnect.vgchartz.com/thread.php?id=229249
Bumb in 2021: http://gamrconnect.vgchartz.com/post.php?id=9047071