Back a year ago, I was running around getting ready for a quest when I was pm-d out of the blue by "Jagex GM Sue".
She said they had been monitoring my chat logs and said I was mature & respectful; did I want to become a player mod?
1st tip-off: no gold crown next to her name.
2nd tip-off: she gave me a website to log into to register.
(Hint: When Jagex was advertising for player mods before, they said they would handle everything through the in-game email system, not in-game chatting or even private emails.)
3rd tip-of: all Jagex people have the "Mod" title in their player names.
So, I was chatty & friendly while I reported her twice (1) impersonating a Jagex person & (2) advertising a website.
Then, I put her on my ignore list and logged out to the lobby. Sure enough, there was no email message from Jagex for me.
I'm letting you all know so you won't fall for this scam where they steal your account.