Xonotlite, or eakleite, is a mineral of general formula Ca6Si6O17(OH)2 named by the German mineralogist Karl Friedrich August Rammelsberg in 1866.

The name originates from its discovery locality, Tetela de Xonotla, Puebla, Mexico.

It is massive, meaning individual crystals are hard to tell apart as they form large masses.

[3] Associated minerals include apophyllite, diopside, stilbite, tobermorite, clinohedrite, thaumasite, laumontite and wollastonite.

It has many type localities, the most notable one being Tetela de Ocampo, Mexico.