Why is Iron the only metal that can be magnetic ? Why only Iron ? What if no one yet had discovered that Iron can be made magnetic, There would be no electricity, aircraft, cars, ships, computers ...... We would all still be in the stone age. One simple discovery changed the world. Would be interesting to know of any similar amazing properties which could be existing in other common metals that we have not discovered yet ?
Another "amazing property" is radioactivity, but that's already been discovered (and exploited). But by definition, if it hasn't been discovered yet, then we couldn't be discussing it because nobody knows about it.
