Factual error: Gollum's body wouldn't sink into the lava if he fell in it as shown in the movie. Rather his body would burst into flames, and turn to ash. Falling in lava isn't like falling into a lake. Lava is more than three times denser than water, which prevents a human shaped body from sinking in.
Suggested correction: Gollum isn't human.
It doesn't matter if Gollum isn't human. Gollum is still a life form with skin organs and bones. Any life form with skin organs and bones would burst into flames and turn to ash if it fell in lava whether it was human or not.
You're talking about the properties of magical metal in a magical volcano in a fantasy movie. Who knows how it will behave?
The entry is talking about what would happen to Gollum realistically if he fell in lava.
It says lava's density prevents a human shaped body from sinking in. It doesn't say it's lava's density prevents a human from sinking in. Gollum's body is the same shape as a human body.
