That is an awesome picture Meagan. I have been doing some research and had not run across that pic so thanks for posting. I have no idea how this color is coming about. Possibly a new mutation. Someone on the Aussie Finch Forum told me about the Opaline Budgies. Opaline Genetics is a sex linked recessive
http://www.budgieplace.com/gen_opaline.html
The body/neck color basically crept up into the head area of this mutation. I haven't found any one yet that knows what is going on with the goulds.... if you ever find info, please do let me know.
As I stated in my post earlier, I wonder if it is not just the food, lighting that is a factor in the vibrancy of the feathers?? Or is it truly a genetic factor. It is only been seen in the sf green pastel (dilute) and the sf blue pastel. (of course males only) I will be keeping records on these boys and their offsprings and maybe will figure it out.
Tiffany has a blue head pastel also and she is very knowledgable on the workings of gouldian genetics so I am sure she will be able to shed some light on the subject as she breeds hers.