itztli (Mdz5r)
This element for obsidian blades (itztli) has been carved from the compound glyph of the personal (ruler's) name, Itzcoatzin. This element involves a series of obsidian blades that were coming off the body of a serpent in the original compound glyph. This explains the unusual shape.
Stephanie Wood
As the "see also" field shows, obsidian blades came in many shapes and colors.
Stephanie Wood
c. 1541, but by 1553 at the latest
Stephanie Wood
itz(tli), a sharp-bladed instrument of obsidian, https://nahuatl.wired-humanities.org/content/itztli
una navaja obsidiana
Codex Mendoza, folio 5 recto, https://digital.bodleian.ox.ac.uk/objects/2fea788e-2aa2-4f08-b6d9-648c00..., image 20 of 188.
Original manuscript is held by the Bodleian Libraries, University of Oxford, MS. Arch. Selden. A. 1; used here with the UK Creative Commons, “Attribution-NonCommercial-ShareAlike 3.0 License” (CC-BY-NC-SA 3.0)