Top 20 Facts in Mineralogy for GATE Geology & IIT JAM Geology
If you’re preparing for the GATE exam, mastering Mineralogy for GATE Geology can give you a big advantage. This guide brings you the top 20 mineralogy facts you must know, along with a free PDF and memory map to help you remember them quickly.
Contents
- Top 20 Mineralogy Facts
- Why Mineralogy is Important in GATE & JAM
- Exam Tips for Mineralogy
Top 20 Mineralogy Facts
- Quartz: Mohs hardness 7, SiO₂ composition, common in igneous, sedimentary, and metamorphic rocks.
- Feldspar Group: Includes orthoclase, plagioclase; framework silicates; Mohs hardness 6.
- Muscovite: KAl₂(AlSi₃O₁₀)(OH)₂, perfect basal cleavage, non-metallic luster.
- Biotite: K(Mg,Fe)₃(AlSi₃O₁₀)(OH)₂, dark mica with perfect basal cleavage.
- Olivine: (Mg,Fe)₂SiO₄, green color, found in mafic and ultramafic rocks.
- Garnet Group: Common varieties include almandine, pyrope, grossular; isometric crystals.
- Calcite: CaCO₃, reacts vigorously with dilute HCl, trigonal system.
- Dolomite: CaMg(CO₃)₂, reacts weakly with cold dilute HCl.
- Magnetite: Fe₃O₄, strongly magnetic, oxide mineral.
- Hematite: Fe₂O₃, red streak, non-magnetic.
- Pyrite: FeS₂, “fool’s gold”, metallic luster, cubic crystals.
- Chalcopyrite: CuFeS₂, brass-yellow, metallic luster.
- Gypsum: CaSO₄·2H₂O, Mohs hardness 2, used in plaster.
- Halite: NaCl, salty taste, cubic cleavage.
- Fluorite: CaF₂, perfect octahedral cleavage, Mohs hardness 4.
- Corundum: Al₂O₃, Mohs hardness 9, gemstone varieties include ruby and sapphire.
- Topaz: Al₂SiO₄(F,OH)₂, Mohs hardness 8, prismatic crystals.
- Kaolinite: Al₂Si₂O₅(OH)₄, clay mineral, earthy texture.
- Galena: PbS, high density, metallic luster, cubic cleavage.
- Graphite: C, greasy feel, good conductor, used in pencils.
Why Mineralogy is Important in GATE & JAM
Mineralogy forms a large portion of the GATE and JAM Geology syllabus. Understanding mineral properties, classifications, and occurrences not only helps in direct questions but also in petrology and economic geology sections.
Exam Tips for Mineralogy
- Focus on physical and chemical properties of major minerals.
- Learn diagnostic features like hardness, cleavage, streak, and luster.
- Memorize common mineral formulas and crystal systems.
- Use memory maps and flashcards for quick revision.
For complete mineralogy preparation with diagrams, solved questions, and memory tricks, check out our GATE Geology Course.
📢 Join our GATE & Geology community on Telegram for daily quizzes, tips, and study resources – Click here to join
