I wonder if it is hydro dip. I know Gruntbull does something they call “Gruntgraphics” that looks like hydro dip but is all anodizing, here are some of their examples:
http://www.gruntbull.com/wp-content/uploads/2016/06/DSC_1895.jpg
http://www.gruntbull.com/wp-content/uploads/2016/06/DSC_1789.jpg
http://www.gruntbull.com/wp-content/uploads/2016/06/Chris-simpsons-portrait.jpg
http://www.gruntbull.com/wp-content/uploads/2016/06/DSC_1745-e1465090998468.jpg
It looks shiny like it could be hydrodip and was done like 6 years before Gruntgraphics were shown off, but I can’t say for sure.