New York, Sep 9 (AZINS) A 13th century Maya document regarded with scepticism since it was reportedly unearthed by looters from a cave in Chiapas, Mexico, in the 1960s is not only genuine but is also likely the most ancient of all surviving manuscripts from ancient America, say researchers.

For years, academics and specialists have argued about the legitimacy of the Grolier Codex consisting of 10 painted pages decorated with ritual Maya iconography and a calendar that charts the movement of the planet Venus. 

"The study is a confirmation that the manuscript, counter to some claims, is quite real. The manuscript was found in a cave in Mexico, and a wealthy Mexican collector, Josue Saenz, had sent it abroad before its eventual return to the Mexican authorities," said Stephen Houston, Professor at Brown University in Providence, Rhode Island, in the US.

Mesoamerican peoples linked the perceived cycles of Venus to particular gods and believed that time was associated with deities, Houston said.

The codex takes its name from the Grolier Club in New York City, where it was displayed in the 1970.

Houston and his co-authors analysed the origins of the manuscript, the nature of its style and iconography, the nature and meaning of its Venus tables, scientific data, the craftsmanship of the codex, and described how the Grolier Codex differs from the three other known ancient Maya manuscripts -- Dresden, Madrid and Pariscodices.

The Grolier's composition, from its 13th-century amatl paper, to the thin red sketch lines underlying the paintings and the Maya blue pigments used in them, are fully persuasive, the authors asserted in a paper published in the journal Maya Archaeology.

The codex is also, according to the researchers, not a markedly beautiful book.

"In my view, it isn't a high-end production, not one that would be used in the most literate royal court. The book is more closely focused on images and the meanings they convey," Houston added.

The researchers also argued that The Grolier Codex is also a 'predetermined rather than observational' guide.

"With its span of 104 years, the Grolier would have been usable for at least three generations of calendar priest or day-keeper," the author wrote.

That makes the Grolier suitable for a particular kind of readership, one of moderately high literacy. It may also have served an ethnically and linguistically mixed group, in part Maya, in part linked to the Toltec civilization centered on the ancient city of Tula in Central Mexico.

Beyond its useful life as a calendar, the Grolier Codex retained its value as a sacred work, a desirable target for Spanish inquisitors intent on destroying such manuscripts.

Created around the time when both Chichen Itza in Yucatán and Tula fell into decline, the codex was created by a scribe working in difficult times. 

Despite his circumstances, the scribe expressed aspects of weaponry with roots in the pre-classic era, simplified and captured Toltec elements that would be deployed by later artists of Oaxaca and Central Mexico and did so in such a manner that not a single detail fails to ring true.

"A reasoned weighing of evidence leaves only one possible conclusion: four intact Mayan codices survive from the Precolumbian period, and one of them is the Grolier," Houston said.