Mining and Mineral Deposits Quiz

What is the formula for calculating profitability in mining?

• Income from selling mined minerals - cost of extraction and processing

• Income from selling mined minerals + cost of extraction and processing

• Income from selling mined minerals / cost of extraction and processing

• Cost of extraction and processing - income from selling mined minerals

Answer explanation

The correct formula for calculating profitability in mining is 'Income from selling mined minerals - cost of extraction and processing'. This shows the net profit after accounting for costs.

What is the term for the rock above the mineral that must be removed?

• Substrate

• Bedrock

• Underburden

• Overburden

Answer explanation

The term 'overburden' refers to the layer of rock or soil that lies above a mineral deposit and must be removed to access the minerals below. This makes 'overburden' the correct answer.

Why are deposits below urban areas usually not mined?

• The minerals are of low quality

• Urban areas have strict environmental laws

• The cost of moving the population is too high

• There are no minerals found in urban areas

Answer explanation

Mining deposits below urban areas is often not feasible due to the high cost of relocating the population. This makes it economically unviable compared to other mining locations.

What happens to mining costs as depth increases?

• They remain constant

• They decrease

• They increase rapidly

• They fluctuate unpredictably

Answer explanation

As mining depth increases, costs rise rapidly due to factors like increased labor, equipment wear, and safety measures. This makes 'They increase rapidly' the correct choice.

What is the 'cut-off ore grade'?

• The average ore purity in a deposit

• The purity level at which mining becomes illegal

• The highest ore purity that can be exploited economically

• The lowest ore purity that can be exploited economically

Answer explanation

The 'cut-off ore grade' refers to the lowest ore purity that can be economically mined. It determines the minimum quality of ore that is viable for extraction, ensuring that mining operations remain profitable.

Which factor does NOT affect transport costs of minerals?

• Market demand

• Ease of bulk transport

• Existing transport infrastructure

• Distance to market

Answer explanation

Market demand does not directly influence transport costs; it affects the price and quantity of minerals sold. In contrast, ease of bulk transport, existing infrastructure, and distance to market directly impact the costs of transporting minerals.

What increases the financial cost of extracting a metal from rock?

• Higher purity of the ore

• Proximity to market

• Lower energy requirements for chemical separation

• Greater quantity of rock to be extracted

Answer explanation

The financial cost of extracting a metal increases with a greater quantity of rock to be extracted, as more resources and labor are needed to process larger amounts, leading to higher overall costs.

What is a consequence of loose overburden?

• Higher ore purity

• Increased risk of landslides

• Lower extraction costs

• Decreased risk of landslides

Answer explanation

Loose overburden can destabilize slopes, leading to an increased risk of landslides. This is because the loose material is less compact and more susceptible to movement under gravitational forces.

What is a challenge when mining minerals found in thin layers?

• Higher market demand

• Lower extraction costs

• Increased size of the mine void

• Reduced environmental damage

Answer explanation

Mining minerals in thin layers often leads to an increased size of the mine void, as more material must be removed to access the minerals. This poses challenges in managing the mine's structure and stability.

What controls the economic viability of exploiting a mineral deposit?

• The type of overburden

• The market demand and sale value of the minerals

• The depth of the deposit

• The purity of the ore

Answer explanation

The economic viability of exploiting a mineral deposit is primarily determined by the market demand and sale value of the minerals. High demand and prices can justify extraction costs, while low values may render it unprofitable.