Hello Molli ,
I read that shiny silver coating makes daguerrotypes special and images are floating on the surface. I am not expert and I have no idea about that polished silver backing is unharmed or not because of treatments.
Did you notice anything like that ? Well lots of us sees old processes at scans whatever it is. I would be happy to see a scan but I dont know how scanner handles reflected intense light.
Thank you Molli and have an wonderful night.