Apparently, "about 10 to about 14 mol % of K2O; from 0 to about 4 mol % of CaO; from about 14 to about 18 mol % of Al2O3; and from about 66 to about 74 mol % Si

Apparently, "about 10 to about 14 mol % of K2O; from 0 to about 4 mol % of CaO; from about 14 to about 18 mol % of Al2O3; and from about 66 to about 74 mol % SiO2" https://patents.justia.com/patent/20220332632 https://patents.justia.com/patent/20220332632 So, an aluminum-potassium-calcium oxide mix instead of the sodium carbonate.