Part of me wants to say, "did you pick up enough Obsidian to make a portal?" - can you guess what I've been playing with my son lots? lol
Never found any of those on my travels. I was shown petrified wood when I was on Ohio though, which was interesting!
I purposely didn't pick up enough obsidian to prevent an interdimensional accident.
If you ever do - see if you can find my pickaxe lol