Could someone please explain to me what a window is in a stone? I am not sure what it is, or what it looks like. Sorry for bothering you all about this.
Here is a blue topaz I picked up at a gem show a few years back. I bought it for $9 just to show what a really poorly cut stone looks like the dead area in the center is a large window. Note that the window is even lopsided. I eventually recut the stone.