Khomyakovite is an exceedingly rare mineral of the eudialyte group, with formula Na12Sr3Ca6Fe3Zr3W(Si25O73)(O,OH,H2O)3(OH,Cl)2.

Khomyakovite is the third eudialyte-group mineral with essential tungsten (after johnsenite-(Ce) and manganokhomyakovite).

[2] Khomyakovite, manganokhomyakovite, johnsenite-(Ce) and oneillite are four eudialyte-group minerals with type locality in Mont Saint-Hilaire, Quebec, Canada.

[5] Khomyakovite itself is associated with analcime, annite, natrolite, titanite, calcite, and pyrite.

[3] Impurities in khomyakovite include niobium, potassium and manganese, with minor rare earth elements, magnesium, titanium, hafnium and aluminium.