Explained Everything on Instagram: "When a glass lid is exposed to high cooking heat, it can crack or shatter due to uneven thermal expansion. The glass heats up faster in some areas than others, creating stress that the material can’t handle. Even tempered glass can fail if the temperature change is too sudden or too high. Glass expands when heated, but different parts expand at different rates Rapid temperature change causes thermal shock and internal stress Tempered glass is stronger but stil