Researchers from Tulane University and the Proyecto Templo Mayor analyzed 788 obsidian artifacts from Tenochtitlan, revealing that the Mexica (Aztec) Empire sourced this important material from at least eight different locations, including regions outside their political control. While 90% of artifacts were made from green obsidian from Sierra de Pachuca (especially for ceremonial purposes), the diversity of obsidian sources suggests sophisticated trade networks rather than just conquest-based acquisition. The study tracked changes in obsidian use from 1375-1520 CE, showing how the Mexica standardized ritual obsidian sources after consolidating power around 1430 CE, providing insights into the empire's economic networks and political influence.

ITHACA, N.Y. – Current methods of capturing and releasing carbon are expensive and so energy-intensive they often require, counterproductively, the use of fossil fuels. Taking inspiration from plants, Cornell University researchers have assembled a chemical process that can power carbon capture with an energy source that’s abundant, clean and free: sunlight.