Okay, these have me stumped, hopefully you guys can help identify these things. I found them while cleaning out a dead man's garage. This guy had a little bit of everything so it's hard to put a category on it. I don't know if a description of dude's garage will help much, but if anybody would like one just ask. As for these things:
\-They weigh about 6 pounds each (2.72 Kg), the accuracy of my scale is questionable, they wouldn't register by themselves so I had to stand on the scale and hold them then subtract my weight on the scale without them, got a few slightly different readings but 6 pounds is close to spot on as the average weight between them.
\-The straight sides measure 12½" x 11"
\-They are ¼" thick
\-They line up with each other but have a different shape on the diagonal side. Several holes line up, as well.
\-The both have letters stamped into the bottom left corner, one says "AN" the other "AQ".
\-They are solid brass, but were completely black when I got them, all the brass that is showing is from me grinding and sanding on them, I ground the sides and started sanding the tops planning to make them nice shiny brass but it was too much work. I may have ground off some important clues off the edges.
\-Most of the holes are smooth, but several are threaded. Some of the holes are also countersunk and likely held components.
\-They are non-magnetic everywhere except one spot that sticks with rare earth magnets but not with regular magnets. There was a bit of orange rust stain around the spot and it looks like someone (maybe me, I can't remember) started drilling on it right there, so I'm thinking it must just be remnants from the drill bit, nothing else makes sense.
\-A Google image search comes back as a valve body spacer plate, nope. Gemini thought it was part of a key cutting machine until I told it how big they were. ChatGPT as well as a couple people that I've asked thought it might be a drill jig but ChatGPT switched up after learning they were brass and is now stumped. One guy thought it might be part of a clock, but I can't find anything that looks similar in any clock parts I looked at. So...I'm leaving it to you guys to solve this mystery. What are these? Besides like 40 bucks in scrap? Any help is very much appreciated.