All-material floors will spawn every type of material, but only of the same level as the area (Max's Area will spawn 1-Star materials, Jackson's will spawn 2-Star, etc). Material-specific floors will only spawn one type of material, but they can spawn as the same level of the area as well as 1-Star above and 2-Stars below.
Fiber materials are an exception, and 1-5 Star Fibers will show up on any floor that can spawn Fiber, regardless of the area.
Certain floors may not always appear, based on tower rotation. See this spreadsheet. Some floors don't spawn any materials at all.
Floors in Bold are connected to the main elevator / return you to the Waiting Room.