My borther-in-law told me that in the mid-1950s, General Motors displayed more at their auto shows than just cars. At one show in Miami , GM featured a display of a million one-dollar bills, as well as the Hope Diamond (the largest blue diamond in the world).
One afternoon a thunderstorm came through the city, lightning flashed, and the lights went out. Immediately truckdrivers with their flashlights rushed to the special display and formed a circle around the armed guards who were already there. The diamond and the cash were now safely guarded with two levels of security.