Night the World Exploded available on YouTube
https://www.youtube.com/watch?v=g8DtpZCJFkY
The print is very good. Too bad, Sam Katzman did not spend a little more effort in making it, as the production values rate from great to horrible (card table chairs on an aircraft and no chem suits in a poison gas environment),as is the science ("element," and "mineral" just do not go together; they should have named it after the park ranger who discovered it, as first suggested).
Nonetheless, "The Night the World Exploded" deserves a remake, as does "Magnetic Monster," which has a similar, but more scientifically plausible storyline.