Sandstone is, of course, the main ingredient in all glass. Mallorytown glass made use of local sandstone which is from the Potsdam sandstone formation, prevalent from Northern New York, Western Québec and Eastern Ontario. This sandstone is of very high purity, being greater than 99% silica. The minor amounts of iron give Mallorytown glass its traditional aquamarine shade. Sandstone is used extensively in the Glassworks permanent exhibit as well. The floor is tile which resembles sandstone, the east wall is covered with four slabs of Potsdam sandstone, obtained from a quarry near Lyndhurst, the donor plaque is backed by the same type of sandstone and pieces of sandstone are located around the exhibit.