When it comes to the art of Erika Mahr and Peggy Johnston, it is fair to say the book should be judged by its cover, its shape and its wacky colors.

On Friday, the double-floor show debuted in the Creative Arts Workshop on 80 Audubon St., which primarily features the works of Mahr and Johnston. Both specialize in making books and were given the chance to exhibit at the Workshop after snagging top honors at the 2010 Inventive Structures competition, an international art show that was titled “Books Beyond the Codex” this year. The exhibition also features work by three “merit recognition” winners and three winners of honorable mentions at the competition. All of the items in the gallery are on sale, with prices ranging from $100 to $6,000.

“The concept behind [Inventive Structures] is nontraditional book forms,” said Lesley Holford, the communications director for the Creative Arts Workshop. “And now in this show, these two artists portray two very different sides of that.”

Mahr’s section of the gallery features a juxtaposition of minimalist style set against the white walls of the room. Her work is entirely in black and white. In the center of the room are black, upwardly bound stacks of paper with centers that are carved out. Flatter books framed on the walls.

Sitting in the center of the space is a piece titled “Descending Grid,” which is a book shaped like a black cube with a miniature staircase cutting through the middle of the book. Like all her pieces, each sheet of paper is meticulously hand cut and is stacked to form a clearly defined geometric structure. More than anything, though, Mahr states in her artist’s statement that she wished to evoke a meditative environment by creating perfect forms.

“This series also explores the unobtainable quest for perfection,” Mahr notes in her statement. “With the restraints of the human body, precision becomes a hopeless ambition.”

But just a quick elevator ride up to the second floor transports the viewer into a room of elaborate and extravagant books — Johnston’s section of the gallery.

“It’s quite a contrast,” said gallery director Diane Svigals. “It’s much more decorative, elegant, and in a way, precious.”

Johnston’s work ranges from books shaped like spinning tops to Asian fans and spans a variety of media, from tea dyed coffee filters to pine needles to heat-warped polyester. But Johnston only named some of her sculptures after the works were completed, giving the abstract forms meanings, Svigals said. She added that after finishing works, Johnston would flip through a picture dictionary to find shapes that resembled her sculptures, and these objects would serve as namesakes for her pieces.

Her largest work sprawls over much of the back wall of the room. Titled “Now Ear This,” the piece features a series of accordion books stretched open with over 100 close-up photographs of ears.

Each book had been packaged in a handmade box for delivery to the exhibition, and these boxes are, in most cases, displayed next to their associated books. Upon purchase of a book, the sculpture is to be repackaged in its box for the new owner to take home.

“She reinvents how books are considered,” Svigals said. “It really is a gift.”

Johnston and Mahr’s exhibition will be on display until Feb. 11.