The Twelve-Angled Stone: A Puzzle in Stone In a quiet alley in Cusco, Peru, sits one of the Inca Empire's most iconic and enigmatic artifacts: the Twelve-Angled Stone. Carved from a single block of andesite, its twelve perfectly cut sides interlock seamlessly with the surrounding polygonal stones of the wall, all without a single drop of mortar. The precision is staggering, defying explanation. How did Inca stonemasons, using only stone hammers and bronze tools, achieve such geometric perfection