Moly Mo Molybdenum Aperture 200um Micron 600um Variable

I have these teeny tiny little disc with a teeny tiny little hole of for auction. The labeling on the bag says molybdenum aperture 200 µm another small bag in the same box at 600 µm and another box with something similar, but the rectangular says a variable aperture 24 to 5 the variable aperture’s. I do not know if they are Moly or some other material. Message me if you have any questions.