Large format glass photo positive. What is it?

Any help with catagorizing this large format (approx. 20" x 18") glass photo would be very appreciated. The image belonged to my grandfather who passed away in 1976, (he was the "collector"), and was handed down to me about 1o years ago. It was broken and I just couldn't bring myself to toss the picture out. At first I thought it was a picture of a stage setting (which it might be), but the young man's shoes seem to be pretty beat up for a stage prop and the furniture looks almost like authentic Shaker to me...but I really don't know...the ruff on the young man's collar throws me off completely!

If you know what kind of photograph this is and when it might have been produced I would be sincerely grateful for the information. I'm considering having it restored; I have all the pieces except the lower right hand corner of the plate.