Diamond and Diamond Grading Practice Exam 2026 - Free Gemology Practice Questions and Study Guide

Block caving is an underground mining method designed for large, low-grade ore bodies near the surface. In this approach, the ore is undercut, and a network of concrete-lined tunnels is established under the deposit. The weight of the overlying rock causes the ore to cave and fracture, and the broken ore is then drawn through openings in the liner—drawpoints or passes—for collection at surface or a central processing area. This system uses gravity to move the ore, enabling very high production with minimal blasting. The other terms don’t describe mining methods—one is a retail term, another a defect, and the last a non- mining concept—so block caving is the correct description for this technique.