A rare pre-Hispanic human skull decorated with a turquoise mosaic is now under the protection of Mexico’s National Institute of Anthropology and History (INAH), a year after its repatriation from the Netherlands.
The skull, believed to be associated with the Mixtec cultural tradition, had spent around six decades at the Wereldmuseum in Leiden before being returned to Mexico.
Since its arrival, INAH specialists have formally registered and inventoried the artefact and produced its first three-dimensional digital record. Authorities are also in discussions with the Yucu Saa Community Museum in Villa de Tututepec, Oaxaca, which has expressed an interest in safeguarding and exhibiting the skull.
The repatriation followed efforts by Mexican institutions and civil society, including the Nohivi Ñuu Savi collective, which advocated for the object’s return.
Mexico’s Secretary of Culture, Claudia Curiel de Icaza, described the recovery as an example of how cooperation between authorities and communities could lead to acts of “historical justice”.
“We recognise the initiative of the Nohivi Ñuu Savi collective, whose work contributed to the return of this artefact to Mexico so that it can be investigated, preserved and reconnected with the memory of the communities,” she said.
Return from the Netherlands
Mexican authorities were first formally notified about discussions surrounding the skull in late 2023, following contact between the Dutch museum and the Mexican Embassy in the Netherlands.
Mexico’s Ministries of Foreign Affairs and Culture subsequently became involved, and in December 2024 the Dutch government, through its Ministry of Education, Culture and Science, finalised arrangements for the object’s return.
The skull arrived in Mexico in May 2025 and was transferred through the Ministry of Foreign Affairs to specialists from INAH’s Directorate of Public Registry of Monuments and Archaeological and Historical Zones for safekeeping.
Alejandro Bautista Valdespino, deputy director of the Registry of Movable Archaeological Monuments, said specialists prepared an archaeological assessment using photographs supplied by the Mexican Embassy and analyses of the skull’s osteological and stylistic characteristics.
The assessment concluded that the remains were pre-Hispanic and originated in what is now Mexican territory, providing the evidence needed to support a formal restitution request.
A Snake Fashioned from Turquoise
The skull is distinguished by an elaborate mosaic covering part of its surface.
Small tesserae form the schematic image of a snake across the frontal bone. The blue pieces are turquoise, while reddish and whitish elements around the brow and eyes are made from shell.
Jadeite survives in the left eye socket, while rock crystal was used for the eye of the depicted serpent.
According to Bautista Valdespino, the technique is documented in Mesoamerica during the Late Postclassic period, between approximately 1200 and 1521 CE, particularly in areas corresponding to the modern Mexican states of Puebla and Oaxaca.
Its precise archaeological origin, however, remains uncertain. The Leiden museum acquired the skull through the art market in 1962, and no detailed information about where it was originally discovered accompanied the acquisition.
Scientific Tests Support Pre-Hispanic Origin
Questions surrounding the skull’s authenticity prompted the Dutch museum, working with the French Center for Research and Restoration of Museums, to undertake scientific investigations in 2011 and 2012.
Isotope analysis, X-ray fluorescence and osteobiographical studies indicated that the skull belonged to a man who was between approximately 25 and 40 years old at the time of his death. Researchers also concluded that the materials used to create the mosaic were pre-Hispanic.
Modern adhesive substances were nevertheless detected in some areas where tesserae had been attached to the skull. Researchers believe this could indicate that parts of the decoration were rearranged or reused before the object entered the museum’s collection.
INAH has since taken additional measures to protect and document the remains. Museum installation technician José Mejía Lozano produced specialist packaging to allow the skull to be handled safely, while photographer Christian Esparza Espinosa created its first three-dimensional digital model.
Researchers Hope to Identify the Person Behind the Mosaic
Scientists say the skull could reveal significantly more about the individual and the society in which he lived.
Physical anthropologist Olaf Bello Cardoso, of INAH’s public registry directorate, said further research could include radiocarbon dating and the study of ancient DNA.
Samples could potentially be obtained from teeth or from the temporal bone, one of the densest parts of the human skull and an important source of preserved ancient DNA.
For researchers, however, the investigation extends beyond establishing the object’s age and biological characteristics.
“From an anthropological perspective, in addition to conducting physical analyses of the skull, it is important to decipher who the person behind the turquoise mosaic is,” Bello Cardoso said.
He pointed to the decorated skull discovered in Tomb 7 at Monte Albán, which formed part of an offering associated with an important individual. A similar motivation may have been behind the ornamentation of the repatriated skull.
“It is possible that the intention was to exalt the individual with the ornamentation of his skull,” he said.
Possible Return to Oaxaca
The next chapter in the skull’s history could take it closer to the region with which its artistic tradition is associated.
INAH is in contact with the Yucu Saa Community Museum in Villa de Tututepec, Oaxaca, after the museum expressed an interest in housing and displaying the artefact.
Bautista Valdespino said INAH would provide institutional guidance to ensure that appropriate conservation, security and exhibition conditions were established before any such transfer took place.
For now, the skull remains under INAH’s protection, where specialists hope its return will enable new research into not only an extraordinary example of Mesoamerican craftsmanship, but also the identity and history of the person whose remains were transformed into it.
Sources : INAH
