Typically an acid etched glass is used. Laminated glass is seldom if ever used in showers.

I ask because the glass is shiny on the outside, usually the matte side is facing out.

No way to be 100% sure, but I did say typically. My office glass is also shiny like that and I happen to have a distraction film. I cannot speak for that project as I we have no way of knowing exactly what was done to the glass.