It's blue in all lights, like I said the pics just don't show what you see in person well. You can see the color a bit better if you look at the animal in Mark's avatar, but it doesn't show the sparkle they have in the sunlight. The male(s) were both called Diamond ( their name ) because of how they sparkled, although they were not "Blue Diamond's" at this point.
I have done a lot of research prior to these and was putting together an article which has been put aside for other reasons regarding them. There are basically two different schools of thought on them, but they all basically originated from the same group.
Also... for the genetics people out there.... I realize that you can't get a Blue Diamond from just a std v/c... but that's how the story goes, there was apparently more genetics going on in there than just that. ;D