1. Which of the following elements are found in the native state?
a) Iron
b) Zinc
c) Gold
d) Lead
View Answer
Explanation: Gold and platinum metals are found principally in the native or metallic form. Iron is found in various minerals; zinc is found in galena and lead is found in galena.
2. Which one of the following is not a mineral?
a) Hematite
b) Sphalerite
c) Coals
d) Cassiterite
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Explanation: Coal, chalk, clay, and granite do not come within the definition of a mineral. Coals are not minerals in the geological sense, but a group of bedded rocks formed by the accumulation of vegetable matter.
3. ______ is a rock formed by the cooling of molten material or magma.
a) Granite
b) Coal
c) Fluorspar
d) Mica
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Explanation: Granite is one of the most abundant igneous rocks, i.e. a rock formed by the cooling of molten material, or magma, within the earth’s crust, is composed of three main mineral constituents, feldspar, quartz, and mica.
4. Which of the following is high-rank coal?
a) Lignite
b) Anthracite
c) Bituminous
d) Peat
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Explanation: The degree of alteration is known as the rank of the coal, the lowest ranks (lignite or brown coal) showing the little alteration, while the highest rank (anthracite) is almost pure graphite (carbon).
5. Minerals exhibit isomorphism.
a) True
b) False
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Explanation: Isomorphism is a property which is exhibited by a mineral or an ore if they have the same crystal structure but different chemical formula. For example, mineral exhibiting isomorphism is albite (NaAlSi3O8) feldspar exhibits isomorphism in which sodium and potassium ions can replace one another.
6. Minerals don’t exhibit polymorphism.
a) True
b) False
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Explanation: Minerals can exhibit polymorphism. For example, graphite and diamond both have the same carbon atoms but the crystallographic arrangement of atoms changes markedly affects their physical properties.
7. _______ metals production rate was highest among the last two decades.
a) Aluminum
b) Copper
c) Iron
d) Zinc
View Answer
Explanation: Aluminum is one of the most widely used meta these days its production grew to 5454 metric tons in 2019. From 1990 to 2000 aluminum production grew by 2700 times whereas 27 times by copper.
8. Which one of the following is not a major factor affecting the cost of metal?
a) Demand
b) Supply
c) Oil prices
d) Cost of virgin metal
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Explanation: Oil prices are one of the major factors that affect the cost of metal, supply includes both virgin metal and scrap and demand is dependent on supply according to the Law of demand.
9. _____ recycling rate is 88%.
a) Steel
b) Aluminum
c) Lead
d) Copper
View Answer
Explanation: Steel is the world’s most recycled material with a recycling rate of 88%, the aluminum recycling rate is 72%, the lead recycling rate is 85% and the copper recycling rate is 35%.
10._____ is the most abundant element on the earth.
a) Oxygen
b) Silicon
c) Aluminum
d) Iron
View Answer
Explanation: Oxygen is the most abundant element on the earth’s crust around 46.4%, Silicon constitutes around 28.2, Aluminum is around 8.2 and Iron is 5.6%.
11. _____ is the most abundant sea- bed mineral.
a) Magnesium
b) Aluminum
c) Iron
d) Copper
View Answer
Explanation: Magnesium has an abundance of 1015-1016 tons in seawater. Silicon, Aluminum, and Iron are around 1012-1013 tons.
12. _____ is the most important and scarce non-ferrous metal.
a) Lead
b) Aluminum
c) Vanadium
d) Copper
View Answer
Explanation: Copper is the most important non-ferrous metal but has a very low percentage in the crust around 0.0055. Aluminum is an abundant non-ferrous metal and Vanadium is a ferrous metal.
13. Most minerals occur along with ______
a) ore
b) metal
c) gangue
d) flux
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Explanation: Gangue is an impurity that frequently occurs along with mineral deposits, metal is extracted from the mineral, flux is added to mineral to remove gangue and ore is a mixture of mineral and gangue.
14. Which one of the following is not a part of the classification of ores based on chemical composition?
a) Oxides ores
b) Sulfides ores
c) Complex ores
d) Sedimentary ores
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Explanation: Oxide, Sulfide, and Complex ores are the classification of ores based on chemical composition. Oxide ores include oxide, carbonate, and hydroxide ores. Sulfide ores include elemental metal along with Sulphur and complex ores have two or more minerals.
Mineral Processing MCQ on Ores, Minerals and Gangues
15. Which one of the following methods is employed for the extraction of metal by the action of heat?
a) Hydrometallurgy
b) Pyrometallurgy
c) Extractive metallurgy
d) Electrometallurgy
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Explanation: Extractive metallurgy deals with any process which extracts metal, pyrometallurgy is the process in which metal is extracted by the action of heat also known as smelting. Electrometallurgy involves extraction by electrical circuits, Hydrometallurgy involves the extraction of metals using solvents.
16. A deposit can be viewed as an ore deposit if the contained value per ton is greater than the costs of processing and other costs per ton.
a) True
b) False
View Answer
Explanation: The Contained value of an ore is the amount of metal present in the ore per ton. Processing cost includes mineral processing costs and metal extraction cost, other costs include logistical costs, etc.
17. _____________ ores are not classified under based on the nature of gangue particles.
a) Siliceous ores
b) Neutral ores
c) Acidic ores
d) Calcareous ores
View Answer
Explanation: Ores are classified based on the gangue particles as only Siliceous ores also known as acidic ores contain high silica content in it and Calcareous ores also known as basic ores have high carbonate content in it. There are no neutral slags.
18. Which one of the following is a major benefit of Mineral Processing / Dressing /Beneficiation?
a) It is a physical process which consumes minimum energy
b) It is located in an area with high transportation facilities
c) It is a very fast process and takes less time
d) Large scale operation requires high capital cost
View Answer
Explanation: The major benefit of mineral processing is a physical process so it doesn’t require heat energy, flux and doesn’t produce slag as in chemical processing. Mine is located near the mine site usually a remote location.
19. Which one of the following has the least abundance (in terms of percentage) among all?
a) Uranium
b) Vanadium
c) Silver
d) Platinum
View Answer
Explanation: Platinum has the least percentage abundance around 5 x 106 percent, and Silver has an abundance of 7×106 percent, Uranium is having an abundance of 0.00027% and Vanadium has 0.014 percentage abundance.
20. Gold ore is estimated profitable even if ore has 1 part per million of the metal.
a) True
b) False
View Answer
Explanation: Gold is estimated profitable even if it has 1ppm of metal in an ore, whereas ores of iron of with greater than 40% metal in the ore are considered to be non-profitable grade.
21. _______ ores have the lowest grade of all mined ores.
a) Platinum
b) Silver
c) Gold
d) Diamond
View Answer
Explanation: The richest mines of the diamond are in Australia with a diamond content of 2 parts per million, whereas the average diamond content in ore of 1.3 ppm is considered very profitable.
22. Which one of the following metals is recovered from the copper tailings by Uranium Corporation of India?
a) Lead
b) Zinc
c) Iron
d) Uranium
View Answer
Explanation: Copper tailings contain a small amount of uranium in it around 0.01% although concentration is very less the large availability of tailings make the process attractive and profitable.
23. Which of the following are polymorphs of Aluminum Silicate?
a) Kyanite, Calcite, and Sillimanite
b) Calcite, Sillimanite, and Aragonite
c) Kyanite, Cristobalite, and Andalusite
d) Sillimanite, Kyanite, and Andalusite
View Answer
Explanation: There are three polymorphs of aluminum silicate they are Sillimanite, Kyanite, and Andalusite. Sillimanite forms at higher temperatures and has an orthorhombic crystal structure, Kyanite forms at high pressure and has a triclinic crystal structure and Andalusite has orthorhombic crystal structure and forms at low temperature and pressure.
24. _____ is the crystal structure of aragonite.
a) Cubic
b) Tetragonal
c) Trigonal
d) Orthorhombic
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Explanation: Aragonite is a polymorph of Calcium Carbonate with the orthorhombic crystal structure, it forms at high temperature. Aragonite is used in the steel making process and is also used in ornaments.
25. Which of the following occurs along with Galena ore?
a) Fluorite
b) Bauxite
c) Feldspar
d) Pyrite
View Answer
Explanation: Galena a major ore for extraction of lead, often occurs with fluorite and barytes, fluorite is used as a flux in smelting operation and barytes are used in the manufacturing of LED glass as it has white color.
Mineral Processing MCQ on Methods
26. What is the mineral dressing operation that is used before the 20th century?
a) Hand-sorting techniques
b) Primary Crushing
c) Grinding
d) Classification
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Explanation: Till the 20th century the mineral processing technology was very primitive and has very little significance. Processing operations were simple hand sorting and gravity separation performed by mining engineers.
27. Mineral processing techniques are useless after the development of pyro and hydrometallurgical processes.
a) True
b) False
View Answer
Explanation: Mineral processing techniques are important even after the advancement of pyro and hydrometallurgy routes. But to make a chemically reactive mineral we need very fine particles. So, we need a combination of both mineral processing techniques and pyro and/or hydro techniques.
28. Two fundamental operations in mineral processing is __________ and ___________
a) liberation, comminution
b) comminution, crushing
c) concentration, liberation
d) liberation, separation
View Answer
Explanation: Liberation and Concentration are two fundamental operations in mineral processing. Liberation involves the release of a valuable mineral from the gangue. Concentration involves the same operation but after grinding step.
29. Which operation uses the greatest energy in concentration operation?
a) Primary crushing
b) Secondary crushing
c) Grinding
d) Intermediate crushers
View Answer
Explanation: Grinding operation often consumes 47% of the concentration operation. Primary crushers consume very less energy compared to all the concentration operations, Secondary and Intermediate crushers consume energy in increasing order.
30. Which of the following techniques is most advanced in the mineral analysis?
a) Optical Microscopy
b) Fluorescence Microscopy
c) Scanning Electron Microscopy
d) X-ray Diffraction
View Answer
Explanation: Scanning electron microscopy like Mineral Liberation Analyzer and QEMSCAN are the most advanced techniques. Whereas, Optical microscopy and fluorescence microscopy are primary techniques of mineral analysis.
31. Which of the following is not an important property in the concentration of ores?
a) Electrical Conductivity
b) Thermal Conductivity
c) Surface properties
d) Magnetic properties
View Answer
Explanation: Thermal conductivity can’t be used in the concentration of minerals. Froth flotation is a process used to exploit the surface properties of a mineral for concentration. Similarly, High-tension separation and Magnetic separation processes are used to increase mineral concentration.
32. ________ is not used for primary crushing.
a) Universal crusher
b) Dodge crusher
c) Cone crusher
d) Gyratory crusher
View Answer
Explanation: Cone crusher is an intermediate crusher, not a primary crusher. Primary crushers are classified as Jaw crushers and Gyratory crushers. Jaw crushers are again classified as Blake jaw crusher, Dodge crusher, and Universal crusher.
33. Which one of the following is the feed material for the Fine crushing?
a) Product of Run of mine
b) Product of primary crushers
c) Product of secondary crushers
d) Product of coarse grinding
View Answer
Explanation: Feed is the incoming mineral to a process. Fine crushing or coarse grinding requires a feed size of 0.5 to 0.2 cm. Run of mine is a feed for primary crushers, a similar product of primary crushers is a feed for secondary crushers.
34. The product of coarse grinding is _________
a) 5 to 0.5 cm
b) 0.5 to 0.01 cm
c) 0.5 to 0.2 cm
d) 75µ (microns)
View Answer
Explanation: The feed size for coarse grinding is 0.5 to 0.2cm and product size is 75µ (microns). 5 to 0.5 cm is product of primary crushers, intermediate crushing product size is 0.5 to 0.01 cm.
35. Flotation costs are the highest in the copper concentrator.
a) True
b) False
View Answer
Explanation: In the Copper concentration process, Flotation requires around 16% of the entire concentration cost. Grinding involves the highest cost around 47% of the entire concentration. Grinding cost is high mainly due to very high-power requirements.
36. _______ bacterium is used as an enhancer to concentrate gold from gold sulfide ores.
a) Acidithio bacillus ferrooxidans
b) Acidiferro bacillus thiooxidans
c) Acidiferro bacillus ferrooxidans
d) Acidithio bacillus thioxidanes
View Answer
Explanation: The rate of oxidation of sulfide ore of gold is improved by the Acidithio bacillus ferrooxidans bacterium. Acidiferro bacillus thiooxidans is used in the biohydrometallurgy of non-ferrous minerals. Acidiferro bacillus ferrooxidans and Acidithio bacillus thioxidanes are used in the biohydrometallurgy of ferrous minerals.
37. An example of separation of minerals based on their difference in densities is the sink and float method.
a) True
b) False
View Answer
Explanation: Sink and Float is a mineral separation process based on the differences in densities of minerals. The sink and float method is used in the processing of iron ore and coal purification. Gravity concentration and heavy media separation also work on the principle of difference in densities.
38. Which of the following is a commercially exploited flocculation phenomenon?
a) Shear Flocculation
b) Oil agglomeration
c) Selective Flocculation
d) Froth Flotation
View Answer
Explanation: Froth flotation is a commercial process used to refine sulfide ores. Shear Flocculation and Selective Flocculation are laboratory-scale separation processes. Oil agglomeration is a selective agglomeration technique but it is not commercially exploited.
39. Which operation comes after Classification in the concentration of magnetite ore?
a) Dry Magnetic separation
b) Wet Magnetic separation
c) Demagnetization
d) Crushing
View Answer
Explanation: Classification is succeeded by wet magnetic separation. Classification is preceded by a Ball Milling operation. Multi Deck Screening is succeeded by crushing and dry magnetic separation.
40. Which one of the following techniques is the most primary mineral processing methods?
a) Hand Sorting
b) Washing
c) Crushing
d) Tabling
View Answer
Explanation: Hand sorting is undoubtedly the oldest method of mineral beneficiation. It is based on the choosing of ore lumps form useless lumps bases on the gross weight and appearance. Hand sorting is still in use where labor is cheap.
41. Which of the following is not an important operation in mineral processing?
a) Crushing
b) Sizing
c) De-watering
d) Concentrating
View Answer
Explanation: Crushing is an operation that comes under comminution operation. The basic operations are Comminution, Sizing, Concentrating and De-watering.
42. Which one of the following is not an Economic advantage of the Mineral Processing.
a) Savings on transportation costs
b) Making the smelting process easier
c) Leads to high slag formation in the smelting process
d) Reduce metal losses in smelting
View Answer
Explanation: The mineral processing main objective is to reduce the gangue particles before the smelting process. Mineral processing directly reduces the fright costs and indirectly limits the high slag formation in the smelting process. Low slag formation means a low metal loss in the smelting process.
43. Which one of the following is not a classification of ore based on the Magnetic properties?
a) Ferromagnetic Minerals
b) Paramagnetic Minerals
c) Non-ferromagnetic Minerals
d) Diamagnetic Minerals
View Answer
Explanation: Minerals are classified based on the Magnetic properties as Ferromagnetic Minerals, Paramagnetic Minerals, Diamagnetic Minerals. Ferromagnetic minerals are highly reactive to a magnetic field like magnetite. Paramagnetic minerals are slightly less reactive to a magnetic field like wolframite. Diamagnetic are poorly reactive to a magnetic field like tin ores.
44. _________ process is applied to convert non-magnetic iron ore to magnesite.
a) Roasting
b) Smelting
c) Calcination
d) Comminution
View Answer
Explanation: Hematite can be converted to magnesite by roasting in a reducing atmosphere. Smelting is a reduction process. Calcination is used to thermally decompose a mineral. Comminution is a size reduction process.
45. High-intensity magnetic separators are used in the processing of magnetite.
a) True
b) False
View Answer
Explanation: Paramagnetic minerals like fayalite require high-intensity magnetic separators. Ferromagnetic minerals or materials are mostly iron-based materials or minerals like iron-titanium oxides and iron sulfides.