Tlaxcallan Blade (IMAGE) North Carolina State University Caption This image shows a fragment of an obsidian blade that had been shaped to a point, collected during the survey of Tlaxcallan. Credit John Millhauser Usage Restrictions Credit must be given. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.