UPSC Prelims 2012 Q86: Science & Technology – Materials & Engineering
Recently, there has been a concern over the short supply of a group of elements called ‘rare
earth metals’. Why?
1. China, which is the largest producer of these elements, has imposed some restrictions on their
export.
2. Other than China, Australia, Canada and Chile, these elements are not found in any country.
3. Rare earth metals are essential for the manufacture of various kinds of electronic items and
there is a growing demand for these elements.
Which of the statements given above is/are correct?
- (a) 1 only
- (b) 2 and 3 only
- (c) 1 and 3 only
- (d) 1, 2 and 3
Answer: (c) 1 and 3 only
Explanation
Short supply of rare earth metals
Rare earth metals are a group of 17 elements: the 15 lanthanides plus scandium and yttrium.
| Statement | Verdict | Reason |
|---|---|---|
| 1. China, which is the largest producer of these elements, has imposed some restrictions on their export | Correct | China then produced over 90 per cent of world supply and cut export quotas around 2010 |
| 2. Other than China, Australia, Canada and Chile, these elements are not found in any country | Incorrect | They are also found in India, the United States, Brazil, Russia and Vietnam |
| 3. Rare earth metals are essential for the manufacture of various kinds of electronic items and there is a growing demand for these elements | Correct | Used in magnets, phones, screens, wind turbines and electric vehicles |
Rare earths and India:
| Point | Detail |
|---|---|
| Source | Monazite in the beach sands of Kerala, Tamil Nadu, Odisha and Andhra Pradesh |
| Producer | IREL (India) Limited, a public sector company |
| Why 'rare' | Not scarce, but seldom found in rich, easily mined deposits |
Answer: (c) 1 and 3 only.
Why each option is right or wrong
- (a) Incorrect. Statement 3 is also true; electronic items need rare earth metals.
- (b) Incorrect. Statement 2 is false; these elements are found in many countries, including India.
- (c) CORRECT. China's export restrictions and rising demand from electronics caused the concern.
- (d) Incorrect. Statement 2 is false; the list of countries is not limited to four.
Key point
Rare earths: 17 elements; China dominates output and has curbed exports; used in magnets and electronics; India's source is monazite sand, processed by IREL.
Remember
Rare earths: 17 elements, China leads, India has monazite.
Common mistakes
- Taking 'rare' to mean found in only a few countries.
- Forgetting that India has rare earths in its beach sands.
- Accepting a statement that says these elements are 'not found in any' other country.
Exam tip
'Not found in any other country' is almost never true of a mineral. Such sweeping statements are safe to reject.
Sources
- Indian Bureau of Mines — Indian Minerals Yearbook (Rare Earths)
- United States Geological Survey — Mineral Commodity Summaries: Rare Earths