A lathe insert holder is missing. I saw it when I taught class two weeks ago, but there is no sign of it now. This is extremely odd, as there is no reason this tool should ever leave the lathe area. The tool is similar to the picture below, but it holds a cutting insert with a different angle/shape.
Still no leads on what happened to this. I will wait a day or two more to see if anyone comes forward. But this is important enough that I will go back through the security camera video to find out what happened if necessary, even if I have to wade through 2-3 weeks of footage to do so.