xiuhtzontli.

Justyna Olko sees xiuhhuitzolli as the "most common term for the turquoise diadem" in the Nahua world. But she also recognizes a term that was practically synonymous, xiuhtzontli ("turquoise hair"), which appears in the Primeros Memoriales and the Anales de Quauhtitlan, f. 28. She also quotes "'in yuhqui xiuhtzontli catca amo quimati in tlein tlazalolli in azo chalchihuitl in anozo xihuitl' ('it was like xiuhtzontli, it is not known what was glued [to it]: maybe jade, or perhaps turquoise'; Anales de Quauhtitlan, fol. 28." (central Mexico, sixteenth century)
Justyna Olko, Insignia of Rank in the Nahua World: From the Fifteenth to the Seventeenth Century (Boulder: University Press of Colorado, 2014), pp. 37, 156, 203.

MOTECUZOMA ILHUICAMINA ixiuhtzon ixiuhyacamiuh ixiuhtilma techilnahuayo itepotzoicpal = MOTECUHZOMA ILHUICAMINA, su diadema de turquesas, su nariguera de turquesa como flecha, su manta color turquesa, festón rojo en la orilla, su asiento con espaldar (centro de México, s. XVI)
Víctor M. Castillo F., "Relación Tepepulca de los señores de México Tenochtitlan y de Acolhuacan," Estudios de Cultura Náhuatl 11 (1974), 183–225, y ver la pág. 196—197.