Post History
I think the others have done a good job of answering the main question of what it would be composed of (I'd have said iron, too, or something similar), so I'll address some of the other stuff. The...
Answer
#1: Attribution notice removed
by
System
·
2020-06-01T14:13:41Z (over 4 years ago)
Source: https://worldbuilding.stackexchange.com/a/5115 License name: CC BY-SA 3.0 License URL: https://creativecommons.org/licenses/by-sa/3.0/