Rock-Forming Minerals Lesson 3 PDF
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NU East Ortigas Senior High School
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This document is a lesson on rock-forming minerals. It details various physical and chemical properties of minerals, and also includes different mineral groups. It could be used as supplementary study material for geological science classes in high school.
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Dwayne ‘The Rock’ Johnson Stone Cold Steve Austin Sen. Ronald ‘Bato’ Dela Rosa Lesson 4.1 Rock-Forming Minerals identify common rock- forming minerals using 1 their physical and At the end chemical properties; of the and...
Dwayne ‘The Rock’ Johnson Stone Cold Steve Austin Sen. Ronald ‘Bato’ Dela Rosa Lesson 4.1 Rock-Forming Minerals identify common rock- forming minerals using 1 their physical and At the end chemical properties; of the and lesson, you should be identify the minerals able to: 2 important to society. Minerals It is a naturally occurring, inorganic, homogeneous solid, with a definite chemical composition, and an ordered crystalline structure. Example of a mineral Physical Properties of Minerals Color refers to certain wavelengths of light that are reflected by a mineral and is perceived by the observer. Streak is the color of the powdered form of a mineral. Luster is the appearance of a mineral’s surface and is dependent on how it reflects light. Crystal habit is the characteristic shape in which a mineral grows and is a projection of the mineral’s crystal structure. Physical Properties of Minerals Cleavage is the tendency of some minerals to break along flat surfaces. Fracture is the pattern in which the mineral breaks aside from its planes of cleavage. Hardness is the resistance of the minerals to scratching. Specific gravity is the ratio of a minerals’ weight to the weight of an equal volume of water. Chemical Properties of Minerals Solubility refers the ability of a substance to dissolve in a solvent at a specified temperature. Melting point refers to the temperature at which solid turns into liquid. Mineral Groups Based on Chemical Composition Chemical Example Description structure Minerals Elements Most of the minerals here are composed of only one element. copper, gold, silver, Having knowledge about elements enables scientists to identify sulfur bonding possibilities and compounds that can be created. Sulfides Minerals under these group are composed of a metal joined by cinnabar (HgS), a sulfur. Metallic luster is the characteristic that distinguish pyrite (FeS2) them. Halides These are nonmetal groups which consists of chlorine, fluorine, fluorite (CaF2), halite bromine, and iodine as their main chemical constituent. (NaCl), diabolite Mineral Groups Based on Chemical Composition Chemical Example Description structure Minerals Oxides and These are mineral groups composed of one or more metals cuprite (Cu2O), hydroxides joined with oxygen, water, or hydroxyl (OH) hematite (Fe2O3) Nitrates, It is formed when a metal is combined with carbon, nitrogen malachite, carbonates, and boron. nitratine, borax borates Sulfates One or more metal is combined with a sulfate compound anhydrite (CaSO4) (SO4) Mineral Groups Based on Chemical Composition Chemical Example Description structure Minerals Chromates, chromate, molybdate, or tungstate substituted the place of wulfenite molybdate, the sulfate group. These minerals are usually brightly (PbMoO4), tungstates colored, brittle and dense. scheelite (CaWO4) Phosphates, One or metal is chemically combined with the Phosphates, apatite, lazulite, arsenates, arsenates, vanadates group. vanadinite vanadates Silicates This is the largest mineral group. Minerals under this group dioptase, have different amounts of silicon and oxygen labradorite Analysis of the Composition and Crystal Structure of Minerals Wet chemical analysis involves dissolving a mineral in an acid and analyzing the solution. Analysis of the Composition and Crystal Structure of Minerals Spectroscopic techniques involve quantitative analysis of mineral components depending on the light absorbance of the compounds. Spectrophotometer Rock Forming Minerals Quartz has a chemical composition of SiO2. It is a glass-like hard substance with white streaks. Feldspar has a chemical composition of XAlSi3O8, where X is potassium (K), calcium (Ca), or sodium (Na). Mica is soft, with hardness ranging from 2 to 2.5. It is easily identified by its perfect cleavage, reducing it to thin smooth flakes. Rock Forming Minerals Pyroxene minerals have a general composition of XY(Al,Si)2O6 where X is calcium (Ca) or magnesium (Mg) and Y is either magnesium (Mg), iron (Fe), or aluminum (Al). Amphibole has a general formula of W0-1X2Y5Z8O22(OH)2 and has a dark color with a Mohs hardness ranging from 5 to 6. It is opaque and has a glassy luster. A mineral is a naturally occurring, inorganic, solid 1 material that has definite chemical composition. The physical properties of minerals are color, 2 streak, luster, crystal habit, cleavage, fracture, hardness, and specific gravity. These properties are used for mineral identification. Solubility and melting point are chemical 3 properties commonly used to describe a mineral. Write true if the statement is correct. Otherwise, write false. 1. A mineral is a naturally-occurring substance. 2. Talc can scratch diamond. 3. A huge mineral has high specific gravity. 4. Bubbles that were formed after pouring an acid to a mineral indicates that the sample is a carbonate mineral. 5. Quartz is a good example of an idiochromatic mineral. You were given two pink minerals (quartz and calcite). Cite ways on how you could distinguish each mineral. TYPES OF ROCK What are Rocks? ◼ A rock is a naturally occurring solid mixture of one or more minerals, or organic matter ◼ Rocks are classified by how they are formed, their composition, and texture ◼ Rocks change over time through the rock cycle Igneous Rocks ◼ Igneous rock comes from magma. ◼Magma can make Igneous Rock: ▪ When rock is heated ▪ When pressure is released ▪ When rock changes composition ◼ Magma cools between 700 °C and 1,250 °C (1300°F). ◼ Magma is a mixture of many minerals. http://www.fi.edu/fellows/payton/rocks/create/igneous.htm Igneous Rocks ◼Felsic: light colored rocks that are rich in elements such as aluminum, potassium, silicon, and sodium. ◼Mafic: dark colored rocks that are rich in calcium, iron, and magnesium, poor in silicon. ◼Intrusive coarse-grained: takes longer to cool, giving mineral crystals more time to grow. ◼Extrusive fine-grained: cools quickly with little to no crystals. Igneous Rocks ◼ Intrusive Igneous Rocks ◼ Extrusive Igneous Rocks http://www.windows.ucar.edu/tour/link=/earth/geology/ig_intrusive.html&edu=high&fr =t Igneous Rocks Coarse-Grain Fine-Grain Felsic Granite Rhyolite Mafic Gabbro Basalt Igneous Rocks Obsidian is a dark-colored volcanic glass that forms from the very rapid cooling of molten rock material. It cools so rapidly that crystals do not form. Is this rock Felsic or Mafic? Is it fine-grained or coarse-grained? Is this rock Intrusive or Extrusive? Sedimentary Rocks ◼ Sedimentary rock is formed by weathering and erosion. ◼ Sediments are moved from one place to another. ◼ Sediments are deposited in layers, with the older ones on the bottom. ◼ The layers become compacted and cemented together. http://www.fi.edu/fellows/payton/rocks/create/sediment.htm Sedimentary Rock ▪ Sedimentary Rocks are formed at or near the Earth’s surface. ▪ No heat. ▪ pressure involved. ▪ Strata – layers of rock. ▪ Stratification – the process in which sedimentary rocks are arranged in layers. Sedimentary Rock Clastic – made of fragments of rock cemented together. Sedimentary Rock Chemical sedimentary – minerals crystallize out of solution to become rock. Limestone: a sedimentary rock composed primarily of calcium carbonate (CaCO3) in the form of the mineral calcite. It most commonly forms in clear, warm, shallow marine waters. It is usually an organic sedimentary rock that forms from the accumulation of shell, coral, algal and fecal debris. Sedimentary Rock Organic sedimentary – remains of plants and animals. Coal: an organic sedimentary rock that forms from the accumulation and preservation of plant materials, usually in a swamp environment. Coal is a combustible rock and along with oil and natural gas it is one of the three most important fossil fuels. THE ARHAEOPTERYX Metamorphic Rock ▪Means to change shape. ▪Changes with temperature and pressure, but remains solid. ▪Usually takes place deep in the Earth. http://www.fi.edu/fellows/payton/rocks/create/metamorph.htm Metamorphic Rocks Contact Metamorphism ◼ heated by nearby magma. ◼ Increased temperature changes the composition of the rock, minerals are changed into new minerals. http://www.windows.ucar.edu/tour/link=/earth/geology/meta_contact.html&edu=h igh&fr=t Metamorphic Rocks Regional Metamorphism ▪ Pressure builds up in rocks deep within the Earth. ▪ Large pieces of the Earth’s crust collide and deform the rock. This is chemically changed by heat and pressure. http://www.windows.ucar.edu/tour/link=/earth/geology/meta_regional.html&edu=high&f r=t Metamorphic Rock ◼ Foliated - contains aligned grains of flat minerals. Gneiss: foliated metamorphic rock that has a banded appearance and is made up of granular mineral grains. It typically contains abundant quartz or feldspar minerals. Metamorphic Rock ◼ Non-Foliated – mineral grains are not arranged in bands or folds. Marble: a non-foliated metamorphic rock that is produced from the metamorphism of limestone. It is composed primarily of calcium carbonate. Metamorphic Rock ◼ Determine if the following rock samples are foliated or nonfoliated: Amphibolite Quartzite Phyllite MARBLE HOUSE 596 Bellevue Avenue, Newport, Rhode Island The ROCK CYCLE BULLPUP ASKS What are your thoughts about MINING? Should mining be abolished? Explain your answer.