According to NASA, the Apollo 11 astronauts left more than the discarded lunar module when they left the Moon. They also left a plaque.
The plaque was attached to the ladder on the strut of the landing gear. It was covered with a thin sheet of stainless steel that was apparently removed after they landed. (They didn’t want it to rust on the way up?) NASA didn’t say what the plaque was made from.
Neil Armstrong was the first man on the Moon, followed by Buzz Aldrin, Jr.; Michael Collins remained in the command module circling the Moon.
45 years ago–nearly half a century.