^I never said he was literally made of rock, any more than I said Reed was literally made of water. It's symbolism. You've really never heard this before? The parallels between CotU and FF, and the shared elemental inspiration, are well-known to comics experts. See here for example:
Of course I've heard of it before. I also heard its not what Lee and Kirby had in mind when creating the FF. The parallels between the FF and the Challs are common knowledge. Kirby played with similar archetypes when creating strips like the Newsboy Legion. Big Words could be a young Reed Richards. Scrapper a young Ben Grimm. Gabby a younger Johnny.
I don't see any elemental inspiration in the Challs. They were just action hero types: Pilot, Diver, Athlete and Daredevil. The elemental inspiration in the FF is just coincidence.