Rocks and Minerals LESSON 2 PDF

******* MINERAL **** ROCK LEARNING TARGET: 1. Classify rocks into Igneous, Sedimentary and Metamorphic; 2. Describe the changes in mineral components and texture of rocks due to changes in pressure and temperature (metamorphism); 3. Compare and contrast the f...

******* MINERAL **** ROCK LEARNING TARGET: 1. Classify rocks into Igneous, Sedimentary and Metamorphic; 2. Describe the changes in mineral components and texture of rocks due to changes in pressure and temperature (metamorphism); 3. Compare and contrast the formation of the different types of Igneous rocks.  Minerals Are naturally-occurring, inorganic solids with crystalline structure and chemical composition which may be fixed or vary within certain limits. MINERALS GENERAL CHARACTERISTICS: Naturally-occurring Inorganic Solid Definite chemical composition Ordered internal structure  CLASSIFICATION BASED ON MINERALS COMPOSITION: Silicates Oxides Sulfides Sulfates Halides Carbonates Native metals MINERALS SILICATES Composed primarily of silicon-oxygen tetrahedrons (SiO4−2) and are major rock-forming minerals. OLIVINE QUARTZ ((Mg,Fe)2SiO4) (SiO2) MINERALS OXIDES Consist of metal cations bonded to oxygen anions MAGNETITE HEMATITE (Fe3O4) (Fe2O3) MINERALS SULFIDES Consist of metal cations bonded to sulfide (𝑆 2−) PYRITE GALENA (FeS2) (PbS) MINERALS SULFATES 2- Consist of a metal cation bonded to the SO4 ) anionic group GYPSUM (CaSO4 2H2O) MINERALS HALIDES Composed of halogen ion, such as, chlorine or fluorine SALT (NaCl) FLUORITE (CaF2) MINERALS CARBONATES 2- Characterized by the presence of carbonic ion (CO3 ) which bonds element such calcium or magnesium DOLOMITE CALCITE (CaCO3) (CaMg(CO3)2) MINERALS NATIVE METALS Consist of a single metal such as copper (Cu) and gold (Au)  PHYSICAL PROPERTIES: MINERALS Color and streak Hardness Cleavage and fracture Crystalline Structure Transparency Magnetism Tenacity Luster Density  MINERALS COLOR AND STREAK Streak is the color of a mineral in its Color is the most evident characteristic powdered form. It can be obtained by and is usually the first property used to rubbing the mineral on an abrasive identify minerals. ceramic tile called streak plate. MINERALS HARDNESS Measurement of the strength of the chemical bonds in its structure MINERALS CLEAVAGE AND FRACTURE The tendency of a mineral to break along planes of weakness  CRYSTALLINE STRUCTURE MINERALS Crystal form is due to mineral’s definite chemical composition. Habit is the outward appearance of the mineral’s crystal form. granular massive tabular reniform dendritic drusy acicular encrusting MINERALS Transparency It indicates the extent of light that can pass through the minerals. Quartz MINERALS Magnetism It indicates the ability of mineral to attract or repel other minerals. Lodestone MINERALS Tenacity Is the mineral’s ability to hold its particles together or the mineral’s level of resistance to stress such as bending, breaking, crushing, or tearing.  LUSTER MINERALS Describes the appearance of light as it is reflected off its surface MINERALS Odor is a distinct smell of a mineral that is usually released from a chemical reaction manifested when the mineral is subjected to water, heat, air, or friction. MINERALS DENSITY Specific gravity is a measure of the density of a mineral Rocks and Rock Cycle  ROCKS Rocks are natural substances consisting of aggregate minerals clumped together with other Earth materials glued by natural processes. Rocks are found in the lithosphere, which derived from the Greek word “lithos” meaning “stone”.  Igneous Are formed from the cooling and solidification of molten or partially Rocks molten volcanic material that came from within the earth like magma. came form the Latin Igneous rocks have many uses. word “ignis” or -Granite, for example, is used for “igneus” which flooring or as table tops. means “fiery” or “fire”  This rocks are the products of the Sedimentary lithification of particles produced by the Rocks weathering of other pre-existing rocks. rocks that have formed from different material deposits on Earth’s surface. came form the Latin word Example of sedimentary rocks are “sedentarius” sandstones, limestones, and shales, which which means are all used in construction materials such as “sitting”. bricks and cement.  are rocks that are formed from igneous Metamorphic or sedimentary rocks that were Rocks exposed to high pressure, high temperature, or a combination of both, deep below the surface of Earth. meta means This rocks are commonly used for building “change” and materials, artwork, and decoration and as components of toothpaste, plastics and morph means paper. Rock such as marble, quartzite, “form” gneiss, and schist. Finding and Mining Minerals An ore is a rock that contains minerals with useful elements. Geologic processes create and concentrate minerals that are valuable natural resources. Geologists study geological formations and then test the physical and chemical properties of soil and rocks to locate possible ores and determine their size and concentration. A mineral deposit will only be mined if it is profitable. A concentration of minerals is only called an ore deposit if it is profitable to mine. Finding and Mining Minerals Mineral deposits are found by geologists by mapping Earth’s surface for clues of valuable minerals. Usually, they look for clues in exposed rocks that may have discoloration or other distinct properties of minerals.  Surface Mining Underground Mining Surface Mining  Surface mining allows extraction of ores that are close to Earth’s surface. It involves the removal and stripping of surface vegetation, dirt, and layers of bedrock to reach the mineral deposits. open-pit mining, strip mining, mountaintop removal mining, and highwall mining  Surface Mining Kennecott Utah Copper’s Bingham Canyon Mine Two-story high haul trucks can carry hundreds of tons of ore.  Surface Mining Albert Frei & Sons Sand Quarry in Idaho Springs, Colorado Rock of Ages Granite Quarry in Barre, Vermont There are two basic types of Mining. Underground Mining  This is a mining technique used to dig tunnels or shafts at greater depths to reach hard mineral deposits like ore that may contain gold, silver, and copper. Underground mining is used to recover ores that are deeper into Earth’s surface. Underground Mining Nickel Miners Underground Drill  Underground Mining Longwall coal mining cuts a slice from the long Notice the safety gear that these miners wear wall. everyday.  Extraction is the process of removing mineral resources from the Earth’s crust. Drilling to set charges for a blast. Carefully controlled blasting breaks up the rock. Blasted ore is hauled to the crusher. Crushers/grinders break up the ore to the size of small pebbles or sand.  Minerals are different, so many different types of processing are needed to remove them from the rock. Following are just a few processes.  Milling This rock contains gold. Milling is the process of separating the desired mineral from the unwanted rock (called gangue.) See if you can find the specks of gold. Concentration and Flotation Some minerals are separated by washing, flotation or magnetic separation. Here a combination of water, chemicals, air and agitation make desired mineral particles float to the top of the bubbles.  Smelting Smelting uses high heat and chemicals to remove base metals and impurities from concentrates. Smelting furnaces can reach temperatures above 1064°Celcius.  Electrowinning Starter sheets are lowered into a solution. An electrical charge passes through causing copper ions to stick to the sheets. Thank you for Listening