Chinchorro mummies took 1.4 kg of manganese a body, and left nothing to explain themselves

The interesting quantity in the new paper is not the pigment but the sequence behind it. Arriaza calls it a chain of operations: locate the stone, collect it, select it, transport it, crush it, process it, mix it with other materials, then apply it to a body that has already been taken apart and rebuilt ^[7]. Sepulveda's remark that no complex technology is needed to gather manganese from surface outcrops is the part worth holding ^[9]. The hard part was never the tool but the order of operations, and holding that order intact for centuries in a society that had no writing to record it ^[3].

How many centuries is where the account strains. The Black Mummy technique is dated to between 4000 and 2800 B.C.E. ^[6], and described in the same account as a technique practiced for nearly two millennia ^[13]. That bracket is 1,200 years ^[16]. Either the dates are conservative or the duration is generous, and the difference is not cosmetic: the whole argument about undocumented technical transmission rests on how long the procedure survived without a written form.

The two procurement stories are not variants of one another. Sepulveda has highland groups mining the mineral and trading it down to the coast, pointing to fish remains, shells and shark teeth found in the Puna de Atacama as the return leg ^[14]. Arriaza allows that the Chinchorro fetched it themselves, and notes deposits along the Lluta River between 5 and 7.5 miles inland and near its Pacific mouth ^[15]. One version needs a standing relationship with people living at nearly 16,400 feet ^[8]; the other needs a walk. The 1.4 kg on the body is the same either way ^[11], but the society it implies is not.

The bodies also work against reading this as elite display. Men, women, the elderly, children and newborns were mummified, from across the social spectrum ^[10]. A technique that tracked state power would be rationed, and this one was applied to infants. What it required instead was skin removal, organ extraction, drying by fire or ash, reconstruction in clay and wool and plant fiber, sea lion skin where the original was insufficient, and a wig ^[5].

Egypt is the reference point for mummification partly because Egypt left buildings and documents that explain it. The Chinchorro left the object and nothing to read ^[3], and the coating on one body is the first part of the process anyone has put a number to ^[1].