true perc getting darker? is it an onyx?

[Purple Penguins]

this little guy is about 3/4" and since I have gotten him between his head line and center line is progressivly getting darker, not sure if he is actually an onyx so thought I would get some opinions.

 

[joker577]

Onyx refers to there being complete blackness between all 3 stripes

 

[Purple Penguins]

yes I thought so too, until I read this thread....
http://reefcentral.com/forums/showthread.php?s=&threadid=1167691

so as far as I can tell there are diff forms of onyx

 

[Tyler.L]

theres no way you can tell really. everything about them on rc first to the second stripe is darker than that and almost complete but just let it color up some more and hope for the best..