KHAY+4.3

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Vocabulary

 * Gemstone:** A mineral that is hard and colorful and has an extraordinary shiny luster
 * Ore:** A type of rock that has a metal or a mineral that is economically useful
 * Smelting:** The development which ore is liquefied to split the useful metal from other elements
 * Alloy:** A hard-core solid mixture of two or more metals
 * Strip mining:** Earthmoving equipment scrapes away from soil to expose ore
 * Open Pit Mining:** Miners use giant earthmoving equipment to dig a tremendous pit
 * Shaft Mines:** often has a network of tunnels that extend deep into the ground,  following the veins

Outline

 * The Uses of Minerals
 * Minerals have been used for many different purposes
 * Gemstones
 * Gemstones are valued for thier beauty, rarity, luster and durability
 * Gems are cut and polished gemstones
 * Metals
 * Metals can be flattened into a sheet, streched to make wires, and hammered or molded without breaking apart
 * Most items we use today are made of metal
 * Other Useful Minerals
 * People use minerals in about everything from fertilizer, foods, medicine, and buildings
 * Talc is used for talcum powder
 * Fluorite is used in aluminun and steel
 * Calcite is used for microscopes
 * Quartz is used in watches, glass, and electrical equipment
 * Kaolin is used in pottery
 * Gypsum is used in cement, wallboards, and stucco
 * Corundum is used in polishing and cleaning products
 * Ores
 * A mineral has to be seperated from its ore before we can use it
 * Prospecting
 * Prospectors look for ores by examining the surroundings
 * They observe all the rocks on the surface
 * They examine plants growing there
 * They test the water (if there is a body of water) for certain chemicals
 * Mining
 * There are three different types of mines: strip mines, open pit mines, and shaft mines
 * Strip mining is done by using earth moving equipment to scrape away the soil to reveal ores
 * Open Pit Mining is done by digging a deep pit to remove the ores
 * Shaft Mining is done underground
 * Mining for metals and minerals harm the earth
 * pollution by waste materials pollute the water
 * digging open the earth leaves scars
 * Mine operaters have to replace the soil and change everything back to normal
 * Smelting
 * After miners remove the ore from a mine, they smelt the ore to remove the metal inside
 * Smelting seperates the useful part of the metal from the rest of the ore
 * First, you mix the ore with other materials (coke and limestone) and then heat the mixture to a hot temperature
 * Next, the heat causes the metal to leave the oxegen which is the reason it is combined with the other rocks
 * Since the added materials create slag, you remove the slag and molten metal through tabs
 * One will carry the slag
 * The other one carries the molten metal