Rating square colors

Noticed that sometimes I get rated with a brown post, that doesn't seem to add or detract from my rating. Comments, if any, generally positive. I am somewhat colorblind, so maybe brown isn't the right color.
Anyway, not so concerned with my rating as wondering what this brown rating is. Didn't see it in the faq, sorry if I missed it. Thanks.

It's gray and it indicates that the rater doesn't have enough rating points to actually affect a rating.

See my "Reps and Rating Posts" link in my signature for all the info on Reps. :)