John, the hallmarks of a shubunkin are that blue background of nacreous scales, the tricolor calico pattern, and scattered metallic scales. The comet that the OP has is completely metallic, with orange and white only. 
For it to be a shubunkin, we would need to see lots of nacreous scales, black patches, and a blue background to the pattern, rather than white. There are some shubunkins that have only white, blue, and black, and they are rather rare and known as Midnight Shubunkins.
And yes, the fish you posted a photo of is mine, and he's an American Shubunkin.
Oh, and I didn't mean to say that the OP's fish is male - I can't be sure from the photos. Could be either gender! But he/she is absolutely gorgeous either way. 
