How is flint created?

Flint is a type of sedimentary rock that primarily consists of silica (silicon dioxide). It forms through the accumulation of microscopic marine organisms, such as diatoms, in sedimentary environments, where their silica-rich remains become compacted and lithified over time. Additionally, flint can also form from the replacement of limestone or chalk through chemical processes, resulting in a hard, dense rock. Its characteristic conchoidal fracture makes it useful for tools and weapons in prehistoric times.