xaltetl.

Headword: 
xaltetl.
IPAspelling: 
ʃɑːltetɬ
Alonso de Molina: 

xaltetl. china o piedrezuela.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 158v. col. 1. Thanks to Joe Campbell for providing the transcription.

Frances Karttunen: 

XĀLTE-TL pl: -MEH whetstone, pumice; gizzard / piedra arenosa (para filar), poma (T), su molleja (Z for possessed form), piedra poma (Z) [(1)Tp.247, (4)Zp.85,98,163]. See XĀL-LI, TE-TL.
Frances Karttunen, An Analytical Dictionary of Nahuatl (Norman: University of Oklahoma Press, 1992), 321.