Inspired by optical illusion artworks, the design of Pyrite bookshelf amazes through an unexpected distribution between empty and full spaces and a structure where horizontal and vertical seems to be reversed. The thin lines of the frame aim for invisibility while contrasting the thicker dividers, in an unusual combination of thicknesses. The different sizes and shapes of the sections combine to give a sense of movement, while drawers in leather or wood can be added to the bookshelf. Pyrite can be used as a single module with two shelves, functioning as a standing alone piece, or it can be combined with others horizontally so to create a larger bookshelf system or either repeated vertically, to cover the length of entire walls.