Asking about the blueness of blue, or anything to do with color, is deliberately misleading. You admit that seeing blue is an event caused by the firing of neurons; the fact that blue light stimulating the retina causes this firing of neurons is largely besides the point. The question is, simply, "How does neurons firing cause us to have a subjective experience?"

The best answer that I think can be given at this point is, "We don't really know, but it's extremely unlikely it involves magic, and if we knew enough to build something that worked almost exactly like our brain, it'd have subjective experience too."

As for the "type" distinction, the idea that blueness in the brain must emerge from some primal blueness, or whatever exactly you're trying to argue, seems like a serious mistake in categories. As another commenter said, there's no chess in deep blue. There's no sense of temperature in a thermostat, no concept of light in a photoreceptor, no sense of lesswrong.com in my CPU. The demand that blueness cannot be merely physical seems to be the mere protestations of a brain contemplating that which it did not evolve to contemplate.