Alibates Flint Quarries National Monument is a U.S. national monument in the state of Texas. For thousands of years, people came to the red bluffs above the Canadian River for flint, vital to their existence. Demand for the high-quality, rainbow-hued flint is reflected in the distribution of Alibates flint through the Great Plains and beyond. Native Americans of the Ice Age Clovis culture used Alibates flint for spear points to hunt the Columbian mammoth before the Great Lakes were formed.