That's fascinating!
One of the guys I dated in the 90s said that many US naval officers got something on their forearms when they crossed the International Date Line. And, the rose on the forearm meant something else as well. One of my bosses had one on his forearm from when he was in the military in the 1980s.
I remember many soldiers who went to Saudi in Desert Storm One got "meat tags." Essentially it was a realistic set of dog tags tattooed on their torso to identify them if their body was blown up or they died.
