Well, you learn something new every day (more, if you’re lucky, and work at it).
Here’s an interesting story for WW II buffs. There were several reasons that Operation Market Garden was a failure, but this is one that I’d never heard before. The troops didn’t get properly reinforced because they couldn’t communicate with radios, due to high concentrations of iron in the ground around Arnhem. It’s the old story of “for want of a nail.” If they’d had satellite phones, the war might have ended months earlier (and the Battle of the Bulge been prevented).