I've had all the Iron Lord artifacts unlocked for over 2 months and never got the achievement until just now. What happened was I was disconnected from Destiny with a WEASEL error code. Instead of pressing B to return to the title screen, I just restarted my console, and started up the game. As soon as I started up the game, instead of going through those logos, I was greeted by a message telling me "Welcome back, you were signed out of Destiny while you were away" or something like that. As soon as I pressed B, a whole bunch of fancy sound effects started up and I got the notification for the Student of History Achievement with a Diamond symbol next to it (first time getting a Diamond Achievement i guess), and was returned to the title screen. Apparently only 2% of players have unlocked this. Am I to assume there is some kind of issue?