Presentation on theme: "Table of Contents Properties of Minerals How Minerals Form"— Presentation transcript:
1 Table of Contents Properties of Minerals How Minerals Form Using Mineral Resources
2 What Is a Mineral? - Properties of Minerals A mineral is a naturally occurring, inorganic solid that has a crystal structure and a definite chemical composition.
3 5 common mineral characteristics Naturally occurringInorganicSolidDefinite chemical composition (i.e. SiO2)Crystal structure*A mineral must have all 5 of these characteristics!*Otherwise the substance is not considered a mineral!
4 Properties used to identify a mineral Color (easily observed but not always accurate)Streak (color of a mineral in powder form)Luster (how light is reflected from the surface of a mineral)Density (mass / volume)Hardness (moh’s hardness scale 1-10)Crystal system (atom arrangement gives the mineral it’s shape)Cleavage (mineral that splits along flat surfaces)Fracture (breaks apart in uneven pattern)Special properties (magnetism, fluorescence, reactivity, etc.)
5 Calculating Density - Properties of Minerals To calculate the density of a mineral, divide the mass of the mineral sample by its volume.Density = Mass/VolumeFor example, if a sample of olivine has a mass of 237 g and a volume of 72 cm3, then the density is237 g/72 cm3 = 3.3 g/cm3Practice ProblemA sample of calcite has a mass of 324 g and a volume of 120 cm3. What is its density?324 g ÷ 120 cm3 = 2.7 g/cm3
6 Mineral Density - Properties of Minerals Use the line graph of the mass and volume of pyrite samples to answer the questions.
7 Mineral Density - Properties of Minerals Reading Graphs: What is the mass of Sample B? What is the volume of Sample B?50 g; 10 cm3
8 Mineral Density - Properties of Minerals Calculating: What is the density of Sample B?5 g/cm3
9 Mineral Density - Properties of Minerals Reading Graphs: What is the mass of Sample C? What is the volume of Sample C?100 g; 20 cm3
10 Mineral Density - Properties of Minerals Calculating: What is the density of Sample C?5 g/cm3
11 Mineral Density - Properties of Minerals Comparing and Contrasting: Compare the density of Sample B to that of Sample C.The density of samples B and C is the same.
12 Mineral Density - Properties of Minerals Predicting: A piece of pyrite has a volume of 40 cm3. What is its mass?8 g
13 Mineral Density - Properties of Minerals Drawing Conclusions: Does the density of a mineral depend on the size of the mineral sample? Explain.No; density does not depend on size. Larger samples have more mass, but the ratio between mass and volume is constant.
14 Identifying Minerals - Properties of Minerals The crystals of each mineral grow atom by atom to form that mineral’s particular crystal structure. Geologists classify these structures into six groups based on the number and angle of the crystal faces.
16 Properties of Minerals OutliningProperties of MineralsAn outline shows the relationship between major ideas and supporting ideas. As you read, make an outline about the properties of minerals. Use the red headings for the main topics and the blue headings for the subtopics.What Is a Mineral?Naturally OccurringInorganicSolidCrystal StructureDefinite Chemical CompositionIdentifying MineralsColorStreakLusterDensityHardnessCrystal SystemsCleavage and FractureSpecial Properties
18 Minerals form by the crystallization of magma and lava - How Minerals FormMinerals form by the crystallization of magma and lavaMinerals also form from crystallization of materials dissolved in water
20 Minerals Generally Form in Two Ways: Minerals can form on the surface through evaporation of solutions containing dissolved minerals.Minerals can also form beneath the surface when dissolved elements and compounds leave a hot water solution or when magma cools and hardens.
21 TerminologyGeodes are hollow rocks that contain crystals inside of themCrystallization is the process where atoms are arranged to form a material with a crystal structure*Crystallization occurs in two ways:From magma slow cooling beneath the surface resulting in larger crystals and from lava quickly cooling resulting in smaller crystals (change from liquid to solid state)From solutions (mixture where one substance dissolves in another)*Crystallization occurs when elements and compounds that aredissolved in water leave a solution*This occurs either through evaporation or from hot water solutionsrepresenting a vein (a mineral deposit found in surrounding rock)
22 Asking Questions - How Minerals Form Before you read, preview the red headings. In a graphic organizer like the one below, ask a how or what question for each heading. As you read, write answers to your questions.QuestionsAnswersHow do minerals form from magma?They form when magma cools and crystals grow.How do minerals form from solutions?They form when solutions evaporate or cool.
23 Using Mineral Resources Minerals are the source of gemstones, metals, and a variety of materials used to make many productsGemstones are hard and colorful minerals with a glassy lusterMetals typically are not as hard as gemstones, but can be stretched out and molded without breakingMinerals can be found everywhere…even in the foods you eat!
24 Producing Metals from Minerals Rocks contain many minerals (including metals) and must be removed from the ground and then processed to extract the metalAn ore is a metal or other useful mineral that can be sold for a profitA prospector is a person who searches for ores to mineA miner is a person who actually extracts the ores for sale at a later timeThere are three type of mines:Strip minesOpen pit minesShaft mines
28 Producing Metals From Minerals - Using Mineral ResourcesProducing Metals From MineralsIn the process of smelting, an ore is mixed with other substances and then melted to separate the useful metal from the other elements the ore contains.
29 Further Processing of Metals Impurities are removed and or additional elements can be added to make a metal stronger.An alloy is a mixture of two or more elements with at least one of the elements being a metal.Example: Steel is produced by adding carbon to iron.*Further processing can result in stronger stainless steel by adding the elements Manganese, Nickel, and Chromium
30 Using Prior Knowledge - Using Mineral Resources Before you read, look at the section headings and visuals to see what this section is about. Then write what you know about mineral resources in a graphic organizer like the one below. As you read, write what you learn.What You KnowThe gems used in jewelry are minerals.Metals come from Earth.What You LearnedMinerals are also the source of metals and other useful materials, like quartz and gypsum.Most metals come from ores, which are mined and smelted before the metals can be used.