Controller of Mines • 2026 • Technical Paper-III
Which reagent is commonly used as a ‘Frother’ in the flotation of sulphide ores?
A)
Xanthates
B)
Pine Oil
C)
Sodium Cyanide
D)
Copper Sulphate
In froth flotation of sulphide ores, a frother is added to stabilize the froth so that the mineral particles can be carried upward. Pine oil is a commonly used frother. Xanthates are collectors, sodium cyanide is a depressant, and copper sulphate is generally used as an activator.
Controller of Mines • 2026 • Technical Paper-III
District Mineral Foundation (DMF) is guided by which scheme for benefit devolution?
A)
National Mineral Exploration Trust (NMET)
B)
PMKKKY
C)
MCDR 2017
D)
Fifth Schedule
District Mineral Foundation (DMF) funds are used for the welfare of people affected by mining, and the guiding framework for benefit devolution is the Pradhan Mantri Khanij Kshetra Kalyan Yojana (PMKKKY). PMKKKY lays down the norms for spending DMF funds for the benefit of mining-affected persons and areas. NMET is for mineral exploration, MCDR 2017 regulates mineral development, and the Fifth Schedule relates to scheduled areas, not DMF benefit devolution.
Controller of Mines • 2026 • Technical Paper-III
According to Stokes’ law, settling velocity in hindered settling is:
A)
g. d2(ρp - ρs) / 18η
B)
(ρp - ρs) / 18η g
C)
3 g.d2
D)
d2
Stokes’ law for the settling velocity of a spherical particle in a fluid is v = g d^2 (ρp - ρs) / 18η, where d is particle diameter, ρp is particle density, ρs is fluid density, g is acceleration due to gravity, and η is viscosity. In hindered settling, the settling is reduced by interaction among particles, but the basic Stokes’ law form given in the options is the correct expression. Options (b), (c), and (d) are incomplete or incorrect expressions.
Controller of Mines • 2026 • Technical Paper-III
What is the minimum No. of persons to be employed when the Owner, Agent or Manager shall constitute a Safety Committee for promoting safety in the mines?
A)
100
B)
200
C)
300
D)
500
Correct option A: 100
Controller of Mines • 2026 • Technical Paper-III
Explain the key objectives of National Mineral Policy, 2019.
Controller of Mines • 2026 • Technical Paper-III
Discuss the role of Indian Bureau of Mines under MCDR, 2017.
Controller of Mines • 2026 • Technical Paper-III
As per the Mines Act, 1952, no adult worker shall be required or allowed to work in a mine above ground for more than how many hours in any week?
A)
40 hours
B)
45 hours
C)
48 hours
D)
54 hours
Under the Mines Act, 1952, an adult worker employed in a mine above ground cannot be required or allowed to work for more than 48 hours in any week. This is the statutory weekly limit for above-ground work. The other options are incorrect because 40, 45, and 54 hours are not the prescribed weekly maximum under the Act.
Controller of Mines • 2026 • Technical Paper-III
According to the Mines Rules, 1955, a First-Aid room must be provided and maintained if the number of persons employed in a mine is more than:
A)
50
B)
100
C)
150
D)
250
Under the Mines Rules, 1955, a first-aid room is required to be provided and maintained when the number of persons employed in a mine exceeds 100. Hence, the correct answer is 100. The other options (50, 150, and 250) do not match the threshold prescribed in the Rules.
Controller of Mines • 2026 • Technical Paper-III
Which of the following authorities is responsible for granting licenses for the bulk storage of explosives under the Explosives Rules, 2008?
A)
DGMS
B)
Indian Bureau of Mines (IBM)
C)
Petroleum and Explosives Safety Organization (PESO)
D)
State Pollution Control Board
Under the Explosives Rules, 2008, licenses for storage and handling of explosives are granted by the Chief Controller/Controllers under the Petroleum and Explosives Safety Organisation (PESO), which functions under the Department for Promotion of Industry and Internal Trade. DGMS deals mainly with mines safety, IBM with mineral administration, and the State Pollution Control Board with environmental clearance/pollution control, not explosives licensing.
Controller of Mines • 2026 • Technical Paper-III
Explain the general safety provisions under Coal Mines Regulations, 2017.
Controller of Mines • 2026 • Technical Paper-III
Under National Mineral Policy, 2019, the State acts as:
A)
Absolute owner of mineral resource
B)
Regulatory authority without fiduciary role
C)
Trustee of mineral resources on behalf of the people
D)
Revenue collecting agency only
Under the National Mineral Policy, 2019, minerals are recognized as a valuable asset of the nation, and the State is expected to act as a trustee of mineral resources on behalf of the people. This reflects the public-trust approach rather than absolute ownership. So (c) is correct. Options (a), (b), and (d) are incorrect because the policy does not treat the State merely as an absolute owner, a bare regulator, or only a revenue-collecting agency.
Controller of Mines • 2026 • Technical Paper-III
A “Serious Bodily Injury” under the Mines Act involves the permanent loss of any part of the body, or loss of sight/hearing, or fracture of any:
A)
Bone or joint
B)
Rib only
C)
Finger only
D)
Skin tissue
Under the Mines Act, 'serious bodily injury' includes permanent loss of any part of the body, loss of sight or hearing, and fracture of any bone or joint. Therefore, the correct option is (a). The other options are incorrect because the law does not restrict the fracture to a rib, finger, or skin tissue.
Controller of Mines • 2026 • Technical Paper-III
The percentage of the mineral occurring as a free particle in the ore in relation to the total content is known as:
A)
Degree of freedom
B)
Degree of bondage
C)
Degree of liberation
D)
Degree of integration
In mineral processing, the percentage of a mineral present as free particles in an ore relative to its total content is called the degree of liberation. It indicates how completely the valuable mineral is separated from the gangue. The other options are not standard terms in this context: degree of freedom is unrelated, degree of bondage is not a mineral processing term, and degree of integration is not used for this definition.
Controller of Mines • 2026 • Technical Paper-III
Under the provisions of the Mines and Minerals (Development and Regulation) Amendment Act, 2015, what is the standard period for which a mining lease for major minerals is now granted?
A)
20 years
B)
30 years
C)
50 years
D)
99 years
Under the Mines and Minerals (Development and Regulation) Amendment Act, 2015, the standard period of a mining lease for major minerals was changed to 50 years. Earlier, leases were generally granted for 30 years. After the 2015 amendment, the lease period was made 50 years, and upon expiry it is generally granted for further periods of 20 years. Therefore, the correct option is (c) 50 years.
Controller of Mines • 2026 • Technical Paper-III
Explain the role and primary functions of the Directorate General of Mines Safety (DGMS) in regulating safety in Indian mines.
Controller of Mines • 2026 • Technical Paper-III
Who is held ultimately responsible for the overall financial and safety compliance of the mine under the Mines Act?
A)
The Mine Foreman
B)
The Manager
C)
The Owner / Agent
D)
The Blaster
Under the Mines Act, the owner/agent is ultimately responsible for the overall control of the mine, including financial and statutory compliance, while the Manager is responsible for day-to-day supervision and safety operations. The Mine Foreman and Blaster have only specific operational duties and are not the ultimate responsible authorities. Hence, the correct answer is the Owner / Agent.
Controller of Mines • 2026 • Technical Paper-III
According to the National Mineral Policy 2019, which of the following is highly emphasized?
A)
Banning all underground mining
B)
Sustainable mining and Zero Waste mining
C)
Exporting all raw minerals
D)
Nationalizing all private mines
The National Mineral Policy, 2019 strongly emphasizes sustainable mining, scientific mining practices, and maximizing recovery of minerals through Zero Waste mining. It aims to balance mineral development with environmental protection and long-term resource conservation. Option (a) is incorrect because the policy does not ban underground mining. Option (c) is incorrect because the policy does not promote exporting all raw minerals. Option (d) is incorrect because it does not call for nationalizing all private mines; instead, it supports a transparent and competitive mineral sector.
Controller of Mines • 2026 • Technical Paper-III
A mining company plans to set aside 20,00,000 today for the future reclamation of a mine site. If the annual interest rate is 10%, calculate the Future Worth of this amount at the end of 4 years, compounded annually.
Controller of Mines • 2026 • Technical Paper-III
What is the present value of Rs. 500 receivable at the end of 5 years, if the discount rate is 10% per annum?
A)
210
B)
310
C)
410
D)
510
Present value (PV) is calculated by discounting the future amount: PV = 500 / (1.10)^5.
(1.10)^5 = 1.61051, so PV ≈ 500 / 1.61051 ≈ 310.46.
However, this does not match option (a). If the question intended simple discounting or a different convention, the closest option is (b) 310. Under standard compound discounting, the correct value is about Rs. 310, so option (b) should be correct.
Controller of Mines • 2026 • Technical Paper-III
Write a short note on Depreciation, Redemption and Depletion.
Controller of Mines • 2026 • Technical Paper-III
As per the Mines Rules, 1955, what is the minimum scale of drinking water to be provided per person employed in a mine?
A)
1 litre
B)
2 litres
C)
3 litres
D)
5 litres
Under the Mines Rules, 1955, the minimum scale of drinking water to be provided per person employed in a mine is 3 litres. Hence, option (c) is correct. The other options are below or above the prescribed minimum scale.
Controller of Mines • 2026 • Technical Paper-III
An equipment costs Rs. 5,00,000. Salvage value after 10 years is Rs. 50,000. Yearly depreciation under straight-line method is:
A)
45,000
B)
50,000
C)
55,000
D)
60,000
Under the straight-line method, yearly depreciation = (Cost of equipment - Salvage value) / Useful life. Here, (5,00,000 - 50,000) / 10 = 4,50,000 / 10 = 45,000. So the correct answer is 45,000. The other options do not match this standard formula.
Controller of Mines • 2026 • Technical Paper-III
Choose the word most nearly opposite in meaning to ABSTEMIOUS:
A)
Self-indulgent
B)
Frugal
C)
Temperate
D)
Moderate
“Abstemious” means sparing and moderate, especially in eating and drinking; self-denying or restrained. The word most nearly opposite is “self-indulgent,” which means giving in to one’s desires and pleasures. The other options—“frugal,” “temperate,” and “moderate”—are close in meaning to abstemious, not opposites.
Controller of Mines • 2026 • Technical Paper-III
Synonym of ‘OBSTINATE’:
A)
Flexible
B)
Humble
C)
Cheerful
D)
Stubborn
“Obstinate” means stubborn, unyielding, or refusing to change one’s opinion or course of action. Among the options, “Stubborn” is the closest synonym. The other options are opposites or unrelated: flexible means adaptable, humble means modest, and cheerful means happy.
Controller of Mines • 2026 • Technical Paper-III
Analogy — LURID: DISMAL::
A)
Lucid: Obscure
B)
Gaudy: Drab
C)
Adroit: Skilful
D)
Ephemeral: Eternal
The relationship is of synonym/near-synonym: 'lurids' means harsh, glaring, or in this context 'dismal/gloomy'. We need the pair with a similar relationship of opposite shades in meaning among the options. 'Gaudy' means showy or excessively bright, while 'drab' means dull and lacking brightness, so they are antonyms and best fit the analogy pattern used in such questions. The other options do not match as well: 'lucid: obscure' and 'ephemeral: eternal' are antonyms, but the given pair is not an antonym pair; 'adroit: skilful' is a synonym pair, not the same kind of relation.
