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Mineral Resources and Mining. 13. CHAPTER. Talk About It Is it important to think about the sources of the minerals we use?. Mining for . . . Cell Phones?. Large reserves of the metal tantalum are found in the Democratic Republic of the Congo, in Africa.
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Mineral Resources and Mining 13 CHAPTER
Talk About ItIs it important to think about the sources of the minerals we use? Mining for . . . Cell Phones? • Large reserves of the metal tantalum are found in the Democratic Republic of the Congo, in Africa. • Tantalum jumped in value in the 1990s as high-tech devices that need tantalum, such as cell phones, became common. • There is international concern regarding the role tantalum mining has played in the extended conflict in the Congo.
Lesson 13.1 Minerals and Rocks Over 4000 minerals have been identified, but only 1% of these are common in Earth’s crust. Amethyst
Lesson 13.1 Minerals and Rocks What Are Minerals? • Occur in nature • Chemically inorganic • Solids • Have orderly crystalline structures • Have definite chemical compositions Pyrite (Fool’s Gold)
Lesson 13.1 Minerals and Rocks Properties of Minerals
Lesson 13.1 Minerals and Rocks Mineral Formation • Minerals can form in four ways: • Crystallization from magma or lava • Precipitation • Pressure and temperature • Production by organisms Salt basins of the Sierra Nevada The Miwok people filled these basins with water from a salt spring and let it evaporate, to form salt for trading. Coral Mineral formed by living things
Lesson 13.1 Minerals and Rocks Mineral Classes • Minerals are classified based on their elements or compounds.
Lesson 13.1 Minerals and Rocks Rocks • Naturally occurring solids made up of minerals and mineral-like materials • Three types: igneous, sedimentary, metamorphic • The rock cycle slowly changes rocks from one type to another through heating, melting, cooling, weathering, and erosion.
Lesson 13.1 Minerals and Rocks Types of Rocks • Igneous: Form when magma cools and solidifies; can be intrusive or extrusive • Sedimentary: Form when sediments cement together or when water evaporates and leaves behind minerals; can be clastic, chemical, or biochemical • Metamorphic: Form when heat or pressure changes the crystalline structure of existing rock Did You Know?In general, the more slowly igneous rock cools, the larger its crystals. Bryce Canyon National Park
Lesson 13.2 Mining More than a ton of waste may remain after extracting just a few hundredths of an ounce of gold.
What Is Mined? Lesson 13.2 Mining • Ores: Groups of minerals that are mined so metal or metals can be removed • Nonmetallic minerals: Minerals, including gemstones, that as a whole have valuable properties • Fuels: Minerals that can be used to generate energy Did You Know?About 100 minerals are considered gemstones, including diamond, topaz, and jade.
Process of Mining and Mineral Use Lesson 13.2 Mining From initial exploration to disposal, mining and mineral use involve many steps.
Mining Methods Lesson 13.2 Mining • Strip mining • Subsurface mining • Open pit mining • Mountaintop removal • Solution mining • Placer mining • Undersea mining A strip mining operation in Wyoming Did You Know?Some subsurface mines in South Africa extend 4 km underground.
Processing Ore Lesson 13.2 Mining • Ores must be processed to gain access to the metals they contain: • Ore is crushed and ground. • Crushed ore is separated into metals and tailings. • Concentrated metals are further processed, often by smelting.
Lesson 13.3 Mining Impacts and Regulation There are about $314 million worth of metals contained in unused cell phones in the United States alone.
Environmental Impacts of Mining Lesson 13.3 Mining Impacts and Regulation • Increased erosion • Sediment and debris clog waterways. • Acid drainage and other forms of water pollution • Air pollution • Disruption of ocean ecosystems (undersea mining) Mine Remediation Mitigation of damage caused to the hillside by strip mining
Social Impacts of Mining Lesson 13.3 Mining Impacts and Regulation • Property damage caused by mountaintop removal or mine collapse • Although mining can bring money and jobs to poor areas of the world, conflicts can arise over mineral rights. • Mining can be hazardous to the health of the miners. Did You Know?Around 650 miners or former miners died from complications related to black lung disease in 2005. Several damaged areas in the Northern Coeur d’Alene Mining District, in Idaho
General Mining Law of 1872 Lesson 13.3 Mining Impacts and Regulation • Created rules to manage mining activity, but also promoted mining • Public land can be claimed and leased from the government for mining. • Claim owners can file to patent, or own, the land for $5 per acre. • Amendments are currently being considered Placer mine on the Hog River, in Alaska
Additional Mining Regulations Lesson 13.3 Mining Impacts and Regulation • Mineral Leasing Act of 1920 governs leasing of public lands for fossil fuel, phosphate, sodium, and sulfur mining. • Surface Mining Control and Reclamation Act (1977) requires that coal-mining companies restore land after mining is complete. An abandoned mine in New York state, now home to hibernating bats
Mine Safety Lesson 13.3 Mining Impacts and Regulation • First law, passed in 1891, established ventilation requirements for coal mines and prohibited miners under 12. • Today, the Federal Mine Safety and Health Act of 1977 regulates mine safety. • In 2010, an underground explosion in a West Virginia mine killed 29 miners.
Responsible Mineral Use Lesson 13.3 Mining Impacts and Regulation • Minerals are nonrenewable resources. • Reducing use, reusing, and recycling minerals can help minimize the negative impacts of mining and address limited supplies. Did You Know?Extracting aluminum ore takes 20 times more energy than obtaining it from recycled sources.