Cooling and solidification without crystal formation is called vitrification. Here is where the nucleation phase of the solidification process takes place. Pure and eutectic metals usually have narrow solidification ranges. It supplies liquid metal to the solidifying casting to compensate for solidification shrinkage. Igneous rock is formed through the cooling and solidification of magma or lava. Intermetallic particles form during solidification of metallic alloys. Cryoprotectant mixtures have been used for vitrification (i.e. solidification without crystal ice formation). These compounds are usually obtained with directional solidification from melt or powder metallurgy processes. This directional solidification improves some metallurgical properties. The alloy does not undergo shrinkage on solidification. It forms from solidification of a magma ocean. Domes undergo various processes such as growth, collapse, solidification and erosion. Sodium aluminate is used in treating water and as an accelerator of solidification of cement. Another commonly used treatment is cement-based solidification and stabilization. There are various Siddha processes formulated in the solidification of mercury.