B. L. Marble Chair

I saved this cool chair from the landfill. I'm having difficult determining its age. The New York State Senate sticker on the underside of the tablet arm is intriguing and make me question whether or not it was designed specifically for the NYS Senate or simply selected from a catalog. I'd like to use it but I'm hesitant to clean it or mildly restore it out of fear of degrading it's value. Does anyone have any resources or information to share with me to learn more about this piece? Also, any cleaning or mild restoration tips? Thanks!