being produced from Trema micrantha from which modern amate is made, the amate found at Huitzilapa is made from Ficus tecolutensis (now F. aurea). Iconography (in stone) dating from the period contains depictions of items thought to be paper. For example, Monument 52 from the Olmec site of San Lorenzo Tenochtitlán illustrates an individual adorned with ear pennants of folded paper. The oldest known surviving book made from amate paper may be the Grolier Codex, which Michael D. Coe and other researchers have asserted is authentic and dated to the 12th-13th century CE. Arguments from the 1940s to the 1970s have centered on a time of 300 CE of the use of bark clothing by the Maya people. Ethnolinguistic studies lead to the names of two villages in Maya territory that relate the use of bark paper, Excachaché ("place where white bark trusses are smoothed") and Yokzachuún ("over the white paper"). Anthropologist Marion mentions that in Lacandones, in Chiapas, the Maya were still manufacturing and using bark clothing in the 1980s. For these reason, it was probably the Maya who first propagated knowledge about bark-paper-making and spread it throughout southern Mexico, Guatemala, Belize, Honduras, and El Salvador, when it was at its height in the pre-classic period. However, according researcher Hans Lenz, this Maya paper was likely not the amate paper known in later Mesoamerica. The Mayan language word for book is hun . Amate paper was used most extensively during the Triple Alliance Empire. This paper was manufactured in over 40 villages in territory controlled by the Aztecs and then handed over as tribute by the conquered peoples. This amounted to about 480,000 sheets annually. Most of the production was concentrated in the modern state of Morelos, where Ficus trees are abundant because of the climate. This paper was assigned to the royal sector, to be used as gifts on special occasions or as rewards for warriors. It was also sent to the religious elites for ritual purposes. The last share was allotted to royal scribes for the writing of codices and other records. Little is known about the paper's manufacture in the pre-Hispanic period. Stone beaters dating from the 6th century CE have been found, and these tools are most often found where amate trees grow. Most are made of volcanic stone with some made of marble and granite. They are usually rectangular or circular with grooves on