I plan to hang a mirror weighing 50lb on the wall. What type of anchors should I use?
I think my wall is plaster over drywall, but I'm not sure. The house was built in the US in 1952, and the surface is very hard. When attempting to hammer in a nail to hang a small photo frame, I gave up after only chipping the surface and bending the nail. There's a small panel in the wall, and the photo below taken from inside the wall shows there's two layers, one light grey on the inside of the wall (drywall?) and one dark grey on the outside (plaster?).
Should I use masonry drill bit to insert a toggle bolt, or find a stud and drill into that, or something else? It seems the options are mutually exclusive if I hit a stud or not, so is a stud finder required for this work?