Chapter 4 section1 what are minerals

Chapter 4: Section1 What Are Minerals?  Minerals –a naturally occurring, inorganic solid that has a crystal structure and a definite chemical composition What Characteristics Does a Mineral Have to Have? A mineral must be:      Naturally Occurring Inorganic Solid Crystal Structure Definite Chemical Composition A What Does It Mean to Be Naturally Occurring? A mineral must occur naturally  Cement, brick, steel, and glass all come from substances found in Earth’s crust but they are manufactured by people How Can Something Be Inorganic?  Inorganic – the mineral cannot arise from materials that were once part of a living thing  Ex Coal is NOT a mineral because it is made up the remains of plants and animals What kind of pattern must a mineral have?  A mineral must have a crystal structure – a repeating pattern of a mineral’s particles that forms a solid  Faces – a crystal’s flat side that meets at sharp edges and corners A What kind of composition must a mineral have? mineral must have a definite chemical composition – it always contains certain elements in definite proportions; most minerals are compounds Cinnabar – composed of the elements Mercury and Sulfur What Is the Difference Between an Element and a Compound?  Element – a substance composed of a single kind of atom Ex Hydrogen  Compound – Two or more elements combined so that the elements no longer have distinct properties Ex Water H20 How Do You Identify Minerals?  Properties:  Density  Crystal Shape  Cleavage and Fracture  Special Properties Hardness Color (this can vary) Streak Luster How Do You Determine a Mineral’s Hardness?  Friedrich Mohs invented a test to describe and compare the hardness of minerals  Mohs Hardness Scale Ranks ten minerals from softest to hardest How Does the Mohs Scale Work? Gypsum (2) will scratch talc (1), calcite (3) will scratch gypsum (2), fluorite (4) will scratch calcite (3), etc What is Mineral Cleavage?  Cleavage –A mineral’s ability to split easily along a flat surface  The ability to break apart depends on the arrangement of the atoms in the mineral Cubic Cleavage Basal Cleavage What is Mineral Fracture?  Fracture – How a mineral looks when it breaks apart in an irregular way What Special Properties does a Mineral have?  Fluorescence –minerals that glow under ultraviolet light  Magnetism - ex Loadstone  Chemical Reactivity- ex Calcite gives off carbon dioxide  Electrical Properties – ex quartz Section2:  How are Minerals Formed? Two General Ways:  Crystallization of melted materials Minerals from Magma  Crystallization in water of materials dissolved Minerals from Hot water Minerals formed by solutions evaporation What is Crystallization?  Crystallization  the process by which atoms are arranged to form a material with a crystal structure How Minerals form from Magma?  Minerals form as magma cools inside the crust, or as lava hardens on the surface What Effects Crystal Size?  Rate at which magma cools Slower cooling forms larger crystals  The amount of gas the magma contains  The chemical composition of the magma How Minerals Form from Hot Water Solutions?  Magma beneath Earth’s surface has heated the water to a high temperature beneath Earth’s surface causing minerals to dissolve  When this solution cools the elements and compounds leave the solution and crystallize as minerals What is a Solution?  Solution – A mixture in which one substance dissolves in another What Pure Metals often form from Hot Water Solutions?  Veins – A narrow channel or slab of a mineral that is much different from the surrounding rock How are Minerals Formed by Evaporation?  As water turns to vapor it leaves behind the mineral  Example: A salt water solution leaves behind large crystals of salt Where are Minerals Found?  Earth’s crust is made up of a variety of minerals however; rare and less common minerals are usually located near plate boundaries because of volcanic activity and mountain building Section 3: How are Minerals Used?  Minerals are the source of Metals ex Aluminum, Iron Gemstones ex Rubies and Sapphires Other Useful materials ex Talc (talcum powder) Ore What?  Ore - A rock that contains a metal or economically useful mineral  Most metals, gemstones, and useful minerals must be separated from their ores What are the Types of Mines?  Strip Mines – Giant equipment is used to scrape away soil  Open Pit Mines – Miners dig a tremendous pit  Shaft Mines – A network of tunnels that extend deep underground [...]... rock How are Minerals Formed by Evaporation?  As water turns to vapor it leaves behind the mineral  Example: A salt water solution leaves behind large crystals of salt Where are Minerals Found?  Earth’s crust is made up of a variety of minerals however; rare and less common minerals are usually located near plate boundaries because of volcanic activity and mountain building Section 3: How are Minerals. .. materials Minerals from Magma  Crystallization in water of materials dissolved Minerals from Hot water Minerals formed by solutions evaporation What is Crystallization?  Crystallization  the process by which atoms are arranged to form a material with a crystal structure How do Minerals form from Magma?  Minerals form as magma cools inside the crust, or as lava hardens on the surface What Effects.. .What Is a Streak Test?  The streak of a mineral is the color of its powder  The streak color and the mineral color are often different  To test: rub a mineral against an unglazed tile (streak plate) What is the Luster of a mineral?  Luster – used to describe how a mineral reflects light from its surface  Minerals containing metals are often shiny  Earthy, waxy, and pearly What does... mountain building Section 3: How are Minerals Used?  Minerals are the source of Metals ex Aluminum, Iron Gemstones ex Rubies and Sapphires Other Useful materials ex Talc (talcum powder) Ore What?  Ore - A rock that contains a metal or economically useful mineral  Most metals, gemstones, and useful minerals must be separated from their ores What are the 3 Types of Mines?  Strip Mines – Giant equipment... Cubic Cleavage Basal Cleavage What is Mineral Fracture?  Fracture – How a mineral looks when it breaks apart in an irregular way What Special Properties does a Mineral have?  Fluorescence minerals that glow under ultraviolet light  Magnetism - ex Loadstone  Chemical Reactivity- ex Calcite gives off carbon dioxide  Electrical Properties – ex quartz Section2:  How are Minerals Formed? Two General... composition of the magma How do Minerals Form from Hot Water Solutions?  Magma beneath Earth’s surface has heated the water to a high temperature beneath Earth’s surface causing minerals to dissolve  When this solution cools the elements and compounds leave the solution and crystallize as minerals What is a Solution?  Solution – A mixture in which one substance dissolves in another What do Pure Metals often... does Density have to do with Minerals?  Each mineral has a characteristic Density  Density – or mass per unit volume; Density = mass/volume  Displacement – the volume of the displaced water equals the volume of the the sample What Kind of Shape does a Mineral have?  Minerals  Cubic have a crystal structure  Hexagonal  Tetragonal  Orthorhombic  Monoclinic  Triclinic What is Mineral Cleavage?