Brown University Archaeologists have unearthed an intact Mayan royal tomb packed with of carvings, ceramics, textiles, and the bones of six children, dating from about 350 to 400 A.D. The tomb, beneath the El Diablo pyramid in the city of El Zotz in Guatemala, was discovered in May, but news was made public Thursday. Layers of mud plaster and stone kept the tomb airtight, and preserved many wood, fiber, and organic materials that will, according to researchers take years to unravel.