1. Hardness 2. Streak 3. Density 4. Crystal structure 5. A mineral must be a naturally occurring, inorganic. 7. c 8. f 9. a 10. d 11. g 12. e 13.

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1 Properties of Guided Reading and Study Use Target Reading Skills Properties of I. What Is a Mineral? A. Naturally Occurring B. Inorganic C. Solid D. Crystal Structure E. Definite Chemical Composition II. Identifying A. Color B. Streak C. Luster D. Density E. Hardness F. Crystal Systems G. Cleavage and Fracture H. Special Properties 1. naturally occurring. 2a. Inorganic b. Solid c. Crystal Structure d. Definite Chemical Composition e. Possible answer: A mineral is naturally occurring, inorganic, and solid. It has a crystal structure and a definite chemical composition. 3. inorganic 4. solid 5. crystal 6. true 7. false 8. compound 9. in a pure form and as part of a compound 10. copper, silver, and gold 11. false 12. true 13. Different minerals may have the same color. 14. streak 15. luster 16. true 17. c, d 18. a scale that ranks ten minerals from softest to hardest 19. talc; diamond 20. false 21. true 22. into six groups based on the number and angle of the crystal faces 23. a 24. c 25. b Properties of Review and Reinforce 1. Hardness 2. Streak 3. Density 4. Crystal structure 5. A mineral must be a naturally occurring, inorganic solid with a crystal structure and a definite chemical composition. 6. Each mineral has its own properties because each mineral has a definite chemical composition. 7. c 8. f 9. a 10. d 11. g 12. e 13. b Skills Lab Finding the Density of For answers, see Teacher s Edition.

2 How Form Guided Reading and Study Use Target Reading Skills This is one possible way to complete the graphic organizer. Accept all logical answers. Question How do minerals form from magma? How do minerals form from solution? Formation of Answer They form when magma cools and crystals grow. They form when solutions evaporate or cool and harden, forming crystals. 1. crystallization 2. by crystallization of magma and lava or by crystallization of materials dissolved in water 3. the rate at which the magma cools, the amount of gas the magma contains, and the chemical composition of the magma 4. It cools slowly over many thousands of years; slow cooling leads to the formation of large crystals. 5. true 6. solution 7. true 8. a, b, d 9. When water is heated to a high temperature, elements and compounds that form a mineral dissolve in the hot water. When the water solution begins to cool, the elements and compounds leave the solution and crystallize, forming minerals. 10. vein 11. Solutions of hot water and metals often flow through cracks within the rock. Then the metals crystallize into veins. 12a. From Magma and Lava b. From Solutions c. Possible answer: Formation of minerals is different because the materials that form minerals can be melted or dissolved. It is the same because both types form through crystallization. How Form Review and Reinforce 1. Magma 2. Elements; compounds 3. crystallize 4. vein 5. In general, minerals can form in two ways: by crystallization of magma and lava and through crystallization of materials dissolved in water. 6. Large crystals are likely to form when magma cools slowly, such as deep underground. Small crystals are likely to form when magma cools rapidly, as when magma cools near the surface or when lava cools. Ocean water seeps down through cracks in the crust, where magma heats it to a high temperature. The hot water dissolves minerals from the crust and rushes upward. The hot solution billows out of vents, or chimneys. When the solution hits the cold sea, minerals crystallize and settle to the ocean floor. 7. Halite deposits form when seawater slowly evaporates. 8. solution 9. geode 10. crystallization How Form Enrich 1. Diamonds are a mineral composed of pure carbon. They are highly valued for their hardness, brilliant luster, and rarity. 2. Diamonds form in the asthenosphere, where high temperatures and intense pressures cause carbon to crystallize. 3. A kimberlite pipe is a long, carrot-shaped crack in the crust with no volcano above it. 4. Kimberlite is a type of rock that contains diamonds and forms when magma cools in a pipe; Kimberlite was named after Kimberley, South Africa, where it was first discovered. 5. Shafts are dug beside the pipe to get to the kimberlite containing diamonds deep underground.

3 Using Mineral Resources Guided Reading and Study Use Target Reading Skills This is one possible way to complete the graphic organizer. Accept all logical answers. What You Know 1. The gems used in jewelry are minerals. 2. Metals come from Earth. What You Learned 1. are also the source of metals and other useful materials, like quartz and gypsum. 2. Most metals come from ores, which must be mined and smelted before the metals can be used. 1. gemstone 2. gem 3. a, c, d 4a. aluminum b. iron c. copper d. silver 5. They can be stretched into wire, flattened into sheets, and hammered or molded without breaking. 6. metal tools and machinery, the metal filament in a light bulb, aluminum foil, and steel beams used to frame office buildings 7. d 8. b 9. c 10. a 11. ore 12. false 13. chalcopyrite 14. prospector 15. They observe rocks on the land surface and study maps of rocks beneath the surface. They map the location, size, and shape of an ore deposit by using the echoes of seismic waves. 16. true 17a. Open Pit b. Shaft c. Strip d. Possible answer: The ore deposits removed in shaft mining occur in veins, similar to the deposits that extend deep underground in open pit mining. The ore deposits removed in strip mining are exposed on the surface, similar to the deposits that start near the surface in open pit mining. 18. Earthmoving equipment scrapes away soil to expose ore. 19. Miners use giant earthmoving equipment to dig a tremendous pit and remove ore deposits. 20. It has a network of tunnels that extend deep into the ground, following the veins of ore. 21. smelting 22. false 23. alloy 24a. mix with limestone and coal b. place in blast furnace c. produce carbon dioxide and molten iron d. pour off molten iron Using Mineral Resources Review and Reinforce 1. Metals 2. Gemstones 3. Quartz 4. Gypsum 5. Strip mines, open-pit mines, shaft mines 6. Answers may vary. A typical answer should mention: (1) iron ore is crushed and mixed with limestone and coke; (2) the mixture is placed in a blast furnace; (3) chemical changes in the furnace produce molten iron and carbon dioxide; (4) iron and slag are produced and poured from the furnace. 7. Alloys are useful because they have special properties. An example is stainless steel, which is an alloy of iron, chromium, and nickel. The special property of stainless steel that is useful is that it doesn t rust. 8. alloy 9. ore 10. smelting Using Mineral Resources Enrich 1. No, alloys can contain two or more metals. For example, aluminum alloys contain aluminum, copper, manganese, and magnesium. 2. A pewter cup contains tin, copper, lead, and antimony. 3. Solder can be used to join metal parts because it has a low melting point. 4. Brass is an alloy of copper and zinc, while bronze is an alloy of copper and tin. 5. Superalloys have great strength and durability.

4 Consumer Lab A Mouthful of For answers, see Teacher s Edition. Key Terms 1. fracture 2. alloy 3. luster 4. inorganic 5. streak 6. smelting 7. crystal 8. compound 9. gemstone 10. solution 11. cleavage 12. element Hidden message: fluorescence

5 Connecting Concepts, formed by magma or by elements or compounds in hot solutions, share five characteristics that make them valuable resources. This concept map is only one way to represent the main ideas and relationships in this chapter. Accept other logical answers from students. color streak luster density hardness ranked by Mohs hardness scale crystal system atoms arrange in process of crystallization can happen with magma and lava solutions to form are identified by have properties of used as way they break gemstones metals come from other uses can be either property ore cleavage fracture processed by smelting naturally occurring inorganic solid crystal structure definite chemical composition

6 Laboratory Investigation How Tessellating! Pre-Lab Discussion 1. Coal is naturally occurring and a solid, but it is not inorganic because it is made from plant matter. There are several types of coal, so it does not have a definite composition. Students may not be aware that coal has no crystal shape. 2. Six Analyze and Conclude 1. Answers will vary. Students might begin with rectangles and diamonds. 2. Circles and ovals won t tessellate. To tessellate, sides must line up. Because circles and ovals have an infinite number of sides, they can t tessellate. 3. Any of the six crystal shapes will tessellate. Many of the shapes will likely be the ones that tessellated for students. Critical Thinking and Applications 1. The pattern repeats without overlaps or gaps. The atoms forming the crystal shape add on in a pattern without overlaps or gaps. 2. Answers will vary. Examples might include title on a floor or bricks on a building. 3. Answers will vary. Sample answer: The patterns are two-dimensional and the crystal shapes are three-dimensional. More to Explore Analyze and Conclude 1. Most likely the shape will have symmetry because it looks the same on either side of a center line. 2. Students may say mineral crystals and bodies of most animals. [Note: Symmetry can be checked with a mirror in the center of the pattern. If the mirror image of the pattern makes it look complete, the pattern has symmetry. Caution students to handle mirrors carefully and to report any breakage to you instead of trying to clean it up.] Performance Assessment 1. A substance needs to be a naturally occurring, inorganic solid with a crystal structure and a definite chemical composition. 2. A mineral s definite chemical composition gives each mineral its own specific properties. 3. Answers will vary. Students could have observed the sample for color, luster, and cleavage/fracture, done a scratch test for hardness, a streak test for streak, and a heft test for density. 4. Students probably had no way of testing for crystal structure or any special properties. 5. Identification will vary, depending on the sample. Students could cite color, luster, cleavage/fracture, streak, and density in confirming an identification. Chapter Test 1. d 2. b 3. c 4. d 5. c 6. a 7. a 8. b 9. d 10. d 11. smelting 12. density 13. shaft 14. halite 15. ore 16. prospector 17. true 18. quartz 19. inorganic 20. true 21. You could not tell them apart with just a scratch test because silver and gold have the same hardness. 22. Pyrite is known as fool s gold because it has the same color and luster as gold. 23. You could do a streak test or determine and compare densities. 24. Quartz occurs naturally, is inorganic, is a solid, has a crystal structure, and has a definite chemical composition. 25. In general, minerals form through crystallization of melted materials and through crystallization of materials dissolved in water. An example of the former is silver; an example of the latter is halite, gypsum, or calcite. 26. form at B as magma slowly cools and hardens, forming large crystals.

7 27. At A, minerals form as salt water evaporates along the shore of a lake or sea that is drying up. At C, minerals form as metals dissolved in hot water solutions come out of solution and crystallize, forming veins. 28. The halite deposit might have formed through the evaporation of salt water from the Great Salt Lake. 29. Slag is a combination of impurities in iron ore and limestone. It forms in a blast furnace once the iron in iron ore has melted and sunk to the bottom of the furnace. 30. The splitting of feldspar at right angles is evidence of the property of cleavage, which only some minerals have. The breaking of quartz into shell-like surfaces is evidence of fracture, a property of most minerals. Neither property alone is enough to enable you to identify a mineral, because other minerals also have these properties, though fewer have the property of cleavage.