How can the shape of a mineral deposit affect mining costs?

The shape and geometry of a mineral deposit are primary factors in determining mining costs, as they dictate the selection of extraction methods, equipment size, and the amount of waste material that must be removed.12

Impact on Mining Operations

• Method Selection: The shape and orientation (such as the dip) of an ore body determine whether a mine can utilize gravity-fed systems or must rely on mechanized transport. For example, steeply dipping deposits may allow for more efficient gravity-based ore movement, whereas flatter deposits require different, often more complex, transport designs.2
• Equipment Constraints: In underground mining, the geometry of the deposit limits the size of the openings (stopes) that can be constructed. If the rock structure contains many defects, openings must be kept small, which restricts the size of mining equipment and reduces productivity. Conversely, larger, more stable ore bodies allow for larger, more productive machinery, which lowers the cost per ton.2
• Development Costs: Because ore development is expensive, miners aim to maximize production (stoping) relative to development work. The shape of the deposit influences how much development is required to access the ore; irregular or thin shapes often increase these costs significantly.2
• Waste Removal: In surface mining, the shape of the deposit relative to the surface determines the stripping ratio—the amount of waste rock that must be removed to access the ore. A shape that requires a wider pit or deeper excavation increases the volume of waste, directly raising total extraction costs.34