Question

Which of the following minerals is/are formed by the process of residual concentration?
A. Iron,
B. Nickel,
C. Copper,
D. Aluminium. Choose the correct answer from the options given below:

• A. A only
• B. A and B only
• C. A, B and C only
• D. A, B and D only

Hint:

Bauxite and nickel laterite are important examples of residual concentration deposits.

Answer 1

The Correct Option is D

Concept:
Residual concentration forms ore deposits by intense weathering and leaching. Soluble materials are removed, while less soluble valuable materials remain concentrated.

Step 1: Iron.
Iron ores may form by residual concentration through lateritic weathering. \[ A \text{ is correct} \]

Step 2: Nickel.
Nickel laterite deposits are formed by residual concentration of nickel during weathering of ultramafic rocks. \[ B \text{ is correct} \]

Step 3: Copper.
Copper is not the typical residual concentration mineral in the given set. \[ C \text{ is not selected} \]

Step 4: Aluminium.
Bauxite, the chief ore of aluminium, is formed by residual concentration. \[ D \text{ is correct} \] Thus, the correct set is: \[ A,B,D \] \[ \therefore \text{Correct Answer is (D)} \]