Frank Lloyd Wright Colored Tree of Life Design Doormat. Constructed in coir fiber pressed into a natural rubber base. Dimensions: 30 inches by 18 inches. Official Frank Lloyd Wright Collection item. The design inspired by several variations of this design with its strong horizontal lines and planes in Wright’s Darwin D. Martin House The Frank Lloyd Wright Colored Tree of Life Design Doormat is inspired by several variations of this design with its strong horizontal lines and planes in Wright’s Darwin D. Martin House. This doormat is constructed in coir fiber pressed into rubber base. The generous proportions of this mat are 30 inches by 18 inches.