The ore is fused with a base, typically sodium carbonate, at around 1000 °C in the presence of air (source of oxygen)::2 Cr2O3 + 4 Na2CO3 + 3 O2 → 4 Na2CrO4 + 4 CO2This step solubilizes the chromium and allows it to be extracted into hot water.
Ampak po navadi je sol vzeta kot dihidrat Na2Cr2O7*2H2O.