PC.B.135 is a spirally grooved tubular bead, collared at both ends and circular in cross section without flattened sides. The internal perforation traversing the bead resulted from boring from both sides, each hole exhibiting longitudinally a conical shape and having different outer diameters. Drilling the cylinder proceeded in stages as the drill bits wore down, and there was a slight deviation in the two opposite courses.
On the exterior surface, the even width of the bands that twirl lengthwise across the shaft of the bead suggests the deployment of a device that enabled both the fixing and the rotation of a solid tube of jadeite while a steady tracking movement with a sharp instrument generated the twisted guide lines. This strongly suggests the synchronized work of two artisans, one rotating the cylinder while the other marked the guide lines. The initial grooves, probably incised after defining the collared ends, were deepened by either repeating the same movement with the rotating device or by etching them manually. The spiral grooves could have been finished first before the cylinder was bored, but their polishing must have been the final manufacturing step.

In Mesoamerica, helical jade beads appear as early as the fourth century CE and in burial contexts. Spirally grooved beads seem to be more common after the tenth century, when they were manufactured from other green stones and obsidian. Most, if not all, spirally grooved beads may have served as personal accoutrements in funerary offerings. Although the examples recovered from the main cenote at Chichén Itzá may be an exception, those found in offerings associated with the Templo Mayor of Mexico-Tenochtitlan occur exclusively in caches containing cremated human remains.

Helical beads may be iconic renderings of ropes or coiled serpents. Their exclusive presence in funerary offerings at the Templo Mayor at Mexico-Tenochtitlan and their occurrence there in pairs or sets of five suggest that they were symbolically related to the path of the soul through the layered cosmos. In Mesoamerican cosmovision, ontological transformations of the body and movements between layers of the cosmos were thought to follow helical paths, as illustrated in the danza del volador, a ritual in which eagle impersonators descend from the top of a tall pole, acting as avatars of the sun in their path to the earthly layer to take offerings of sacrificial victims.

Benson, Elizabeth P. 1963 Handbook of the Robert Woods Bliss Collection of Pre-Columbian Art. Dumbarton Oaks, Trustees for Harvard University, Washington, D.C., p. 25, cat. 119.

Bliss, Robert Woods 1947 Indigenous Art of the Americas: Collection of Robert Woods Bliss. National Gallery of Art, Smithsonian Institution, Washington, D.C., p. 14, 79, cat. 51.

Bliss, Robert Woods 1957 Pre-Columbian Art: The Robert Woods Bliss Collection. Text and Critical Analyses by S. K. Lothrop, Joy Mahler and William F. Foshag. Phaidon, New York. p. 247, cat. 92, pl. LVIII.

Bliss, Robert Woods 1959 Pre-Columbian Art: The Robert Woods Bliss Collection. 2nd ed. Text and Critical Analyses by S. K. Lothrop, Joy Mahler and William F. Foshag. Phaidon, London. p. 255, cat. 92, pl. LVIII.

Solís Olguín, Felipe R. 2004 The Aztec Empire: Catalogue of the Exhibition. Guggenheim Museum Publications, New York. p. 43, cat. 184.

"Indigenous Art of the Americas", National Gallery of Art, Washington DC, April 1947 to July 1949, November 1952 to July 1962.

"The Aztec Empire", Guggenheim Museum, New York, NY, 10/14/2004 - 2/13/2005; Guggenheim Museum, Bilbao, Spain 3/15/ - 9/4/2005.

"The Aztec World", Field Museum, Chicago IL, 10/26/2008 - 4/19/2009.

Purchased from Earl Stendahl, Los Angeles (dealer), by Robert Woods Bliss, 1942.

Robert Woods Bliss Collection of Pre-Columbian Art, Washington, DC, 1942-1962.

Dumbarton Oaks Research Library and Collection, Pre-Columbian Collection, Washington, DC.