Creating the card set would have been a hazardous job. For the gilding, its designers used mercury, a poisonous substance that can potentially kill.
“You ground up gold into kind of a dust, and you mix it with mercury, and you painted that onto the surface where you wished the gilding to appear,” Schroder told LiveScience in an interview. The mercury gets burned off in a kiln, a process “that would leave the gold chemically bonded to the silver.”
The process is illegal today, he noted, and even in Renaissance times, it was known to be hazardous. “I don’t think they quite understood why it was dangerous, but they did appreciate the dangers of it,” Schroder said.
Story: Owen JArus, LiveScience | Photo: Patrick Debremme