tetl (Mdz51r)
This element of a tetl (stone) has been carved from the compound sign for the place name, Itztecoyan. It is a classic design, horizontal with curling ends and wavy, alternating, purple and terracotta- or orange-colored stripes. The end on the right is orange, and the end on the left is purple (or purplish-gray).
Stephanie Wood
This design will endure (if not as perfectly and not colored) almost twenty years later in the Matrícula de Huexotzinco. For example, see the personal name Tetl from 622 recto or Tepixqui from 638 recto, below. When tetl is merged with other elements in compound glyphs, sometimes it is just the curling ends that appear, as we see in Tetlacuilol and Tetl Iacon. This is what leads me to see the curling edges of mountain as providing the te- start to tepetl.
c. 1541, by 1553 at the latest
stones, rocks, piedras
la piedra
Stephanie Wood
Codex Mendoza, folio 51 recto, https://digital.bodleian.ox.ac.uk/objects/2fea788e-2aa2-4f08-b6d9-648c00..., image 112 of 118.
The Bodleian Libraries, University of Oxford, hold the original manuscript, the MS. Arch. Selden. A. 1. This image is published here under the UK Creative Commons, “Attribution-NonCommercial-ShareAlike 3.0 License” (CC-BY-NC-SA 3.0).