Amazon.com description: Product Description: A unique book that brings together two of the most important expressions of the pre-Hispanic era: The Aztec Calendar and the solar symbol Nahui Ollin . Time has transformed the Aztec Calendar into a symbol associated with ruthless human sacrifices performed by the Mexicas. Well-documented studies by these two talented scholars uncover the true purpose of the stone and the historical events which resulted in the creation of this marvelous monolith. This is the only book that brings together photographs from other important solar monuments from multiple private collections and various museums around the world. To date, there is no other book that provides such a precise and fascinating description of the meaning of the Aztec Calendar and of Nahui Ollin. The book includes a unique booklet with six transparencies which in full colour highlight each of the six concentric circles of the Aztec Calendar.