Xiuhhuacan (Mdz38r)
This simplex glyph for turquoise (xihuitl) stands for the place name Xiuhhuacan. The visual source for the "hua" (possession) syllable is unclear. The locative suffix (-can) is not shown visually. The sign is basically round with an inner circle that has two small compartments painted red, and around the outer circle are four evenly-place smaller circles. All but the two red compartments are painted turquoise.
Stephanie Wood
The shape suggests a gleaming turquoise stone, but it could also share a reading of "year." Sometimes, the turquoise part of this glyph could be filled with small pieces of turquoise mosaic, such as has been published from a cache found at the Templo Mayor. Small turquoise pieces were easier to come by, and so they were often assembled in mosaic fashion. [See: J. Alden Mason, "Turquoise Mosaics from Northern Mexico," Museum Journal (Penn Museum), 20:2 (1929).]
Stephanie Wood
c. 1541, but by 1553 at the latest
xiuhpohualli, año, turquesa, xihuitl
xihui(tl), turquoise, https://nahuatl.wired-humanities.org/content/xihuitl
-hua-, possession or containment, https://nahuatl.wired-humanities.org/content/hua
-can (locative suffix), https://nahuatl.wired-humanities.org/content/can-2
Codex Mendoza, folio 38 recto, https://digital.bodleian.ox.ac.uk/objects/2fea788e-2aa2-4f08-b6d9-648c00..., image 86 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)