Consider the following minerals: In India, which of the above is/are officially designated as major minerals?

Answer: (d) 2, 3 and 4 only

Chromite, kyanite and sillimanite are major minerals.

Statement by statement

1. ✗ MINOR Bentonite (a clay) is a minor mineral, like sand and building stone.

2. ✓ MAJOR Chromite is a major mineral.

3. ✓ MAJOR Kyanite is a major mineral.

4. ✓ MAJOR Sillimanite is a major mineral.

The idea

“Major” and “minor” are legal mineral categories, not a ranking by price, weight or usefulness. A valuable industrial mineral can still be placed in the minor category by notification. The date of the classification matters when applying it to an old question.

Why the others are wrong

(a) Includes bentonite.

(b) Drops chromite and kyanite.

(c) Includes bentonite.

The trap

Minor minerals (sand, clay, stone) are regulated by States; major minerals by the Centre.

Also know

Chromite supplies chromium for stainless steel. Kyanite, sillimanite and andalusite are closely related aluminium-silicate minerals used in heat-resistant materials. Bentonite is a swelling clay used in drilling fluids and foundry work. Industrial use alone cannot establish the applicable concession rules.