What are these large pieces of plexiglass?

Question

I found these large, heavy pieces of plexiglass while cleaning the shed on the property of a house that I just bought. I have no idea what they are or what they are used for. They are about the size of a kitchen table and if there wasn't 6 of them back there, I would have guessed it was an old table top. As you can see from the pictures, they are very dirty, but from what I know about plexiglass, pieces this size do not come cheap.

The 6th piece is on the right side of the other 5. It seems to be of higher quality, you can see from the pictures that it is more clear. It is also heavier. It also has a crease around the edges of it that you can see in the pictures. I thought it was real glass at first based on its weight and hardness.

Any idea what these are and what they are used for?

Click for full size

Answer 1

They look like high-end desk chair mats, perhaps for use on carpet.

Answer 2

I doubt that they were meant as chair mats. That old plexiglass would not make a good one, being too prone to break and scratching and coloring very quickly under normal use (Polycarb wasn't around then). Plus there were better, cheaper alternatives.

The edge-groove in that one sheet suggests an attempt at an edge-mounting bevel. The fact that there were several suggests spares or repeated application.

I'd guess that these were intended for windows with a "60's look" -- having seen similar once upon a time.

Answer 3

It is almost impossible to know their original intended usage. Perhaps they were "windows" in a set for some old play, then removed and saved after the set was torn down.

My guess is the person scavenged then from some application like that, then kept them hidden away in case they ever found a new use. That you found them still hidden says they never did find a use, and that you won't either. However, I'll bet that you can sell them on Craigslist or ebay. Or bring them to your local auction house, where all sorts of things like this get sold.