Why is cassiterite the most important commercial ore of tin?

Cassiterite is the most important commercial ore of tin because it is the only tin mineral of significant economic value. As a naturally occurring oxide of tin ($Sn{O}_2$), it contains approximately 78.8 percent tin, making it a highly efficient source for the metal.12

In the context of tin processing, the metal is extracted from cassiterite through a reduction process, which involves removing the oxygen using coal or coke in smelting furnaces. While other complex sulfide minerals like stannite and cylindrite exist, they are of far less importance compared to the widespread and relatively concentrated nature of cassiterite deposits.12