Sources in the Valley of Mexico, which fell under Teotihuacan control during the Early Classic, were Pachuca, Otumba, and Chicoloapan. Obsidian from Pachuca is notable because of its unique green-gold color and its internal purity which makes it one of the highest quality obsidian sources in Mesoamerica. It was much sought after and widely traded. Green obsidian is also found in the area of Tulancingo, but is distinct from Pachuca obsidian because of its internal opacity (e.g., it is a more milky or clouded green).