What kind of exterior panels are these?

I have always loved the deco style, and vintage modern homes and while out traveling today me and the family came across this small rural town on a part of the original Route 66, it had ALOT of amazing homes in it, especially for being sub a small town, it was like a different world being that almost everything was beautifully restored or preserved, out of the normal style homes. One in particular jumped out at us and I have never seen a exterior panel finish like this, and was wondering if any of you had seen this or know what kind of panels these are. They were a gloss finish, almost porcelain looking but obviously aren't. Any help?