of mortar on most structural projects. The Mayas used a very difficult process of limestone under large amounts of heat to create their mortar. The mortar was so widely used, the Mayas even used it for sculptures, facades, and floor layers. Their mortar was very effective on a large building lifetime, but humid climates can have a negative effect on the mortar. For more important construction projects the Mayas would cover the entire structures exterior with stucco, followed by bright paintings, prioritizing red, yellow, green, and blue. Notable constructions Ceremonial platforms These were commonly limestone platforms of typically less than four meters in height where public ceremonies and religious rites were performed. Constructed in the fashion of a typical foundation platform, these were often accented by carved figures, altars and perhaps tzompantli, a stake used to display the heads to the victims or defeated Mesoamerican ballgame opponents. Palaces Large and often highly decorated, the palaces usually sat close to the center of a city and housed the population's elite. Every exceedingly large royal palace, or one consisting of many chambers on different levels might be referred to as an acropolis. However, often these were one-story and consisted of small chambers and typically at least one interior courtyard; these structures appear to take into account the needed functionality required of a residence, as well as the decoration required for their inhabitants stature. Archaeologists seem to agree that many palaces are home to various tombs. At Copán (one of the most powerful and important cities), beneath over four-hundred years of later remodeling, a tomb for one of the ancient rulers has been discovered and the North Acropolis at Tikal appears to have been the site of numerous burials during the Terminal Pre-classic and Early Classic periods. E-groups "E-Group" is a classification given by Mayanists to certain structure complexes present at a number of Maya sites located in the central and southern Maya lowlands (e.g., the Petén region). Complexes of this type consist of a stepped pyramid main structure, situated on the western side of a quadrilateral plaza or platform. A raised but rather elongated structure appears along the eastern side of the plaza, running north–south; a variation has three smaller temple mounds on top of or replacing this platform, the middle of these substructures placed directly opposite the main structure. Often, two other subsidiary structures appear on the north and south sides