It wasn't till the third hole that he noticed the three iron would not go all the way into the golf bag. it was suspicous enough that he had his other golf clubs brought out. The security team emptied the bag and found a small hunk of uranium ore in it. Trump had been touching the club that had been exposed to uranium.
Uranium is bad. Trump knows all about it.
“You know what uranium is, right? It’s this thing called nuclear weapons. And other things. Like lots of things are done with uranium. Including some bad things. But nobody talks about that.”
It appears that it may have been there for years, as Trump remembers some sort of rocks falling in there when he golfed in Utah.