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Then there is a neutralization/timing process just to stop the (basic) processing fluid after some point, and to make the photo safe to handle/abuse (unused film is caustic inside). Those layers are on the exposure side and are just clear to the eye.
If you delayer one of these photos, you can see the rear window (clear/slightly tinted), clear gel-like acid/neutralization layers, pitch black processing fluid remnant, and then a shadow of the image from the rear side after you get rid of all the black goop.
If you keep rubbing under water, you can see that the emulsion layers hold dye in the negative pattern of the image (the parts that didn't make it through), and if you're careful you can rub down to the light-reflective layer (white) without destroying the photo.
That leaves you with a slightly translucent, rather delicate photo with a white back (it's pretty easy to scratch it from the rear). The dyes in the image-receiving layer do seem to retain a bit of layering too (cyan/magenta/yellow are not in the same exact plane).
What I find most impressive here is that the white/black layers between the emulsion/dyes and image receiving layer seem quite solid and are obviously opaque, yet the dyes do migrate cleanly to the other side (and there is no trace of the dyes visible in that white layer itself).
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