Colored portraits and Gem in the Explained!

[edit] Please pardon the typo in the title XD

So I think I figured it out.

There are 5 colors of rank besides the starting noob blue.

It goes, Emerald Green, Blue-ish Green, Platinum Rank Color-ish, Red, and Gold.

So that covers levels 1-599.

After that, the colored portraits start over, but this time they have a gem. So levels 600-1099 have a single gem, with the colored portrait procession of before.

Then two gems and so forth.

I hope that helps!