Well, when I pledged (in 2005) and looked at all the pins, I was determined to have the yellow gold diamond pin...so I bought it all by myself!  I just got two dangles for mine, since I was just named Director of Ritual for Alpha Psi.  I love to wear my badge as much as I can, and while I do so many people ask about it and have stories to tell of their own.  The way I look at it, my diamond badge is sort of a literal and figurative "investment" in my sorority...I have a picture of it and I'd love to post it...but sorry, I don't know how!  I can't figure out how to attach it properly, even with the FAQ. 
