User blog comment:Litlmamaini/Mysterious Crystals!!/@comment-5303258-20121009030831

I bet they are from tapjoy. I have had to email them about not receiving crystals and they just credited my account without saying anything. And just so you know, there is a challenge in the 60's that gives you the phoenix as a reward. Don't waste 550 crystals on something you will get later. Doesn't seem worth it. Just a thought though.