The Cascajal Block is a writing tablet-sized serpentinite slab which has been dated to the early first millennium BCE incised with hitherto unknown characters that may represent the earliest writing system in the New World. Archaeologist Stephen D. Houston of Brown University said that this discovery helps to "link the Olmec civilization to literacy, document an unsuspected writing system, and reveal a new complexity to [the Olmec] civilization."
The Cascajal Block was discovered by road builders in the late 1990s in a pile of debris in the village of Lomas de Tacamichapa in the Veracruz lowlands in the ancient Olmec heartland. The block was found amidst ceramic shards and clay figurines and from these the block is dated to the Olmec archaeological culture's San Lorenzo Tenochtitlán phase, which ended c. 900 BCE, preceding the oldest Zapotec writing dated to about 500 BCE. Archaeologists Carmen Rodriguez and Ponciano Ortiz of the National Institute of Anthropology and History of Mexico examined and registered it with government historical authorities. It weighs about 11.5 kg (25 lb) and measures 36 cm × 21 cm × 13 cm. Details of the find were published by researchers in the 15 September 2006 issue of the journal Science
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