Minerals Quartz Apatite Diamond hardness color Topaz fracture Gypsum talc Minerals luster Corundum density Orthoclase Calcite Fluorite cleavage

EQ: What is a mineral? Standard: S6E5.b Investigate the contribution of minerals to rock composition.

EQ: What is a mineral? What is a mineral? What is a crystal, and what determines a crystal’s shape? Describe the two major groups of minerals. What is a native element?

Mineral Structure A mineral is a naturally formed, inorganic solid that has a definite crystalline structure. Minerals may be either elements or compounds. Elements are pure substances that cannot be broken down into simpler substances by ordinary means. A compound is a substance made of two or more different elements that have been joined together by a chemical bond.

(5) Characteristics of Minerals Naturally Formed- must form naturally, not man-made Inorganic- cannot arise from materials that were once part of a living thing Solid- always solid, not a liquid or gas. It has a definite volume and a definite shape Crystalline Structure- particles must line up in a pattern that repeats over and over again Definite Chemical Composition- always contains certain elements in definite proportions. NaCl (salt)

Mineral Structure A few minerals, such as gold and silver, are composed of only one element. A mineral that is composed of only one element is called a native element. Native elements are used in communications, and electronics equipment.

What is a Mineral?

Crystals A crystal is a solid whose atoms, ions, or molecules are arranged in a definite pattern. Crystals are solid, geometric forms produced by a repeating pattern of atoms or molecules that are present throughout the mineral. A crystal’s shape is determined by the arrangement of the atoms or molecules within the crystal. All minerals can be grouped into crystal classes according to the kinds of crystals they form.

Crystalline Structure of a Mineral

Two Groups of Minerals Minerals are divided into two groups based on their chemical composition. Silicate minerals are minerals that contain a combination of the elements silicon and oxygen (quartz, feldspar, mica). Silicate minerals make up over 90% of the Earth’s crust. Nonsilicate minerals are minerals that do not contain a combination of the elements silicon and oxygen ( copper, calcite, fluorite, corundum, gypsum, galena).

Common Silicate Minerals

Classes of Nonsilicate Minerals

Quick Check What are the two major groups of minerals? metallic and nonmetallic native elements and carbonates silicates and nonsilicates quartz and mica

Quick Check Which of the following is NOT a characteristic of a mineral? a. It is formed in nature. b. It is a living material. c. It has a crystalline structure. d. It is a solid.

Quick Check A mineral that contains a combination of silicon, oxygen, and other elements is a crystal. Silicate mineral. nonsilicate mineral. element.

Quick Check Which of the following is a nonsilicate mineral? orthoclase, KASi3O8 Talc, Mg3Si4O10(OH)2 Almandine, Fe3Al2(SiO4)3 Magnetite, Fe3O4

Quick Check A solid whose atoms, ions, or molecules are arranged in a definite pattern is called a a. silicate mineral b. element. c. Crystal. d. nonsilicate mineral.

Quick Check A mineral that does not contain compounds of silicon and oxygen is called a a. mineral. b. silicate mineral. c. compound. d. Nonsilicate mineral.

Quick Check A substance that cannot be separated or broken down into simpler substances by chemical means is called an a. Element. b. crystal. c. mineral. d. compound.

Quick Check A naturally formed, inorganic solid that has a definite crystalline structure is called a a. silicate mineral. b. nonsilicate mineral. c. crystal. d. Mineral.

Quick Check A substance made up of atoms of two or more different elements by chemical means is called a a. silicate mineral. b. mineral. c. Compound. d. element.

EQ: How are minerals identified? What is the Moh’s hardness scale? What is the major difference between an element and a compound?

Properties of Minerals A mineral is a naturally formed, inorganic solid that has a crystal structure and a definite chemical composition. Each mineral has its own set of specific physical properties that can be used to identify it (hardness, color, streak, luster, density, crystal system, cleavage and fracture). An element is a substance composed of a single kind of atom. A compound is two or more elements combined so that the elements no longer have their original distinct properties.

Identifying Minerals Hardness- Moh’s scale ranks ten minerals from softest to hardest. Resistance to scratch Color- Because of factors, such as impurities, used only to identify a few minerals Streak- the color of a mineral in its powdered form Luster- how a mineral reflects light from its surface Density- the ratio of the mass to the volume of a substance Crystal Systems- six groups of structures based on the number and angle of the crystal faces Cleavage – splitting along smooth, flat surface Fracture- breaking apart along curved or irregular surfaces

Mohs Hardness Scale Talc 1 Softest known mineral Gypsum 2 fingernail can scratch it Calcite 3 scratched by copper penny Fluorite 4 easily scratched by steel knife Apatite 5 can be scratched by steel knife Orthoclase 6 can scratch window glass Quartz 7 can scratch steel Topaz 8 can scratch quartz Corundum 9 can scratch topaz Diamond 10 hardest known mineral

Moh’s Hardness Scale

Special Properties Some properties are particular to only a few types of minerals: Fluorescence – glow under ultraviolet light Chemical Reactions – reacts to an acid Magnetism – natural magnets that attract iron. Taste – ex. Halite has a salty taste Optical Properties – some can cause a double image Radioactivity – minerals that contain radium or uranium

Special Properties of Some Minerals

Quick Check Which of the following properties of minerals does Moh's scale measure? luster density hardness streak

Quick Check Pure substances cannot be broken down into simpler substances by ordinary chemical means are called a. molecules. b. compounds. c. crystals. d. elements.

Quick Check Which of the following properties is considered a special property that applies to only a few minerals? a. luster b. taste c. hardness d. density

Quick Check The appearance of a material that can vary according to the impurities in that mineral as well as other factors: a. density b. cleavage c. hardness d. streak e. color f. luster

Quick Check The splitting of a mineral along smooth, flat surfaces: a. density b. cleavage c. hardness d. streak e. fracture f. luster

Quick Check the ratio of the mass of a substance to the volume of the substance: a. density b. cleavage c. hardness d. streak e. fracture f. luster

Quick Check A measure of the ability of a mineral to resist scratching: a. density b. cleavage c. hardness d. streak e. fracture f. special properties

Quick Check Characteristics that are particular to only a few types of minerals: a, cleavage b. hardness c. special properties d. streak e. color f. luster

Quick Check The color of the powder of a mineral: a. density b. cleavage c. hardness d. streak e. special properties f. color

Quick Check The way in which a mineral reflects light: a. density b. cleavage c. hardness d. streak e. fracture f. luster

Quick Check The breaking of a mineral along either curved or irregular surfaces: a. density b. cleavage c. hardness d. fracture e. luster f. special properties

The Formation, Mining, and Use of Minerals (p.74) If you wanted to find a mineral, where do you think you would look? Compare surface and subsurface mining. What is mine reclamation? What are some examples of minerals and their uses?

The Formation of Minerals Minerals form in a variety of environments in Earth’s crust. Each of these environments has a different set of physical and chemical conditions. The environment in which a mineral forms determines the mineral’s properties. Environments in which minerals form may be on or near Earth’s surface or deep beneath Earth’s surface.

Formation Environments

The Environments Evaporating Salt Water When a body of salt water dries up, minerals are left behind. (gypsum, halite) Metamorphic Rocks Where minerals form when rocks are altered by changes in pressure, temperature, or chemical make-up. (calcite, garnet, graphite, hematite, magnetite, mica, and talc)

The Environments Limestone Rocks formed when surface water and ground water carry dissolved materials to lakes and seas where they crystallize on the bottom (calcite, dolomite) Hot-Water Solutions Environment in which groundwater works its way downward and is heated. Groundwater works its way downward and is heated by magma and then reacts with minerals. (gold, copper, sulfur, pyrite, galena)

The Environments Pegmatite Teardrop-shaped bodies with large crystals, such as gemstones, that form when magma moves upward. (many gemstones, such as topaz, tourmaline) Plutons Magma body that moves upward and cools before it reaches the surface, forming crystals; . (mica, feldspar, magnetite, quartz)

Mining An ore is the natural material large enough and pure enough to be mined for profit. Rocks and minerals are removed from the ground by one of two methods-surface mining and subsurface mining. Surface mining is used to remove mineral deposits on or near the Earth’s surface. - open pits - surface coal mines (open-pit) - quarries

Mining Subsurface mining is used when mineral deposits are located too deep within Earth to be surface mined. Mine reclamation is the process by which land used for mining is returned to its original state or better. Has been required by law since the mid-1970’s. To reduce the effects of mining, reduce our need for minerals, reuse, and recycle.

Surface Mining This quarry in northwest Georgia is an open pit used to mine granite.

Subsurface Mining Subsurface mining is the removal of minerals from DEEP within the Earth. Passageways must be dug underground to reach the ore.

The Use of Minerals Some minerals are of major economic and industrial importance. Metallic minerals have shiny surfaces, do not let light pass through them, good conductors of heat and electricity. Nonmetallic minerals have shiny or dull surfaces, may let light pass through them, and are good insulators of electricity.

The Use of Minerals Gemstones are highly valuable minerals because of their beauty and rarity rather than their usefulness. Color is the most important characteristic of a gemstone. The more attractive the color is, the more valuable the gem is. Mass of a gem is expressed in a unit known as a carat. One carat is equal to 200 mg.

Gemstones The Cullinan Diamond, at the center of this scepter, is part of the largest diamond ever found.

Common Uses of Minerals Copper Electrical wires, plumbing, coins Diamond Jewelry, cutting tools, drill bits Galena Batteries, ammunition Gibbsite Cans, foil, appliances, utensils Gold Jewelry, computers, spacecraft, dentistry Gypsum Wallboards, plaster, cement Halite Nutrition, highway de-icer, water softener Quartz Glass, computer chips Silver Jewelry, photography, electronic products Sphalerite Jet aircraft, spacecraft, paints

Some Material Used in the Parts of a Bike

Quick Check Teardrop-shaped bodies with large crystals, such as gemstones, that form when magma moves upward. (many gemstones, such as topaz, tourmaline) A. metamorphic rocks B. evaporating salt water C. limestones D. pluton E. hot-water solutions F. pegmatites

Quick Check A. metamorphic rocks B. evaporating salt water Environment in which groundwater works its way downward and is heated Groundwater works its way downward and is heated by magma and then reacts with minerals. (gold, copper, sulfur, pyrite, galena) A. metamorphic rocks B. evaporating salt water C. limestones D. pluton E. hot-water solutions F. pegmatites

Quick Check Rocks formed when surface water and ground water carry dissolved materials to lakes and seas where they crystallize on the bottom (calcite, dolomite) A. metamorphic rocks B. evaporating salt water C. limestones D. pluton E. hot-water solutions F. pegmatites

Quick check Environment in which body of salt water dries up (gypsum, halite) A. metamorphic rocks B. evaporating salt water C. limestones D. pluton E. hot-water solutions F. pegmatites

Quick Check Magma body that moves upward and cools before it reaches the surface, forming crystals; . (mica, feldspar, magnetite, quartz) A. metamorphic rocks B. evaporating salt water C. limestones D. pluton E. hot-water solutions F. pegmatites

Quick Check A. metamorphic rocks Where minerals form when rocks are altered by changes in pressure, temperature, or chemical make-up. (calcite, garnet, graphite, hematite, magnetite, mica, and talc) A. metamorphic rocks B. evaporating salt water C. limestones D. pluton E. hot-water solutions F. Pegmatites

Quick Check the process of returning land to its original condition after mining a. metallic mineral b. surface mining c. reclamation d. ore

Quick Check the removal of minerals that are located at or near the surface of the earth a. metallic mineral b. surface mining c. reclamation d. ore

Quick Check a mineral deposit that is large and pure enough to be mined for profit is called? a. metallic mineral b. surface mining c. reclamation d. ore

Quick Check a mineral that has a shiny surface, does not let light pass through, and is a good conductor of heat and electricity a. metallic mineral b. surface mining c. reclamation d. ore