Presentation on theme: "6.E.2.1 Summarize the structure of the earth, including the layers, the mantle and core based on the relative position, composition and density."— Presentation transcript:
6.E.2.1 Summarize the structure of the earth, including the layers, the mantle and core based on the relative position, composition and density.
A geode is a rounded, hollow rock that is often lined with mineral crystals. Crystals form inside a geode when water containing dissolved minerals seep into a crack or hollow in a rock. Slowly, crystallization occurs, lining the inside with large crystals that are often perfectly formed.
Crystallization is the process by which atoms are arranged to form a material with a crystal structure.
Minerals From Magma and Lava Many minerals form from magma and lava. Minerals form as hot magma cools inside the crust, or as lava hardness on the surface. When these liquids cool to a solid state, they form crystals. The size of the crystals depends on several factors. * the rate at which the magma cools * the amount of gas the magma contains * the chemical composition of the magma
Minerals From Solutions Sometimes the elements and compounds that form minerals can be dissolved in water to form solutions. A solution is a mixture in which one substance is dissolved in another. When elements and compounds that are dissolved in water leave a solution, crystallization occurs. Minerals can form in this way underground and in bodies of water on Earth’s surface.
Minerals Formed by Evaporation Some materials form when solutions evaporate. If you stir salt crystals into a beaker of water, the salt dissolves, forming a solution. But if you allow the water in the solution to evaporate, it will leave salt crystals on the bottom of the beaker. Halite, gypsum, and calcite are a few minerals that form by evaporation.
Minerals From Hot Water Solutions Deep underground, magma can heat water to a high temperature. When the water solution begins to cool, the elements and compounds leave the solution and crystallize as minerals.
Minerals form on the surface through evaporation of solutions containing dissolved minerals. Minerals can form beneath the surface when dissolved elements and compounds leave hot water solution or when magma cools and hardens. Where Minerals Form
Using Mineral Resources You are surrounded by materials that come from minerals, such as the metal body and window glass of a car. Minerals are the source of gemstones, metals, and a variety of materials used to make many products.
Gemstones Usually, a gemstone is a hard, colorful mineral that has a brilliant or glassy luster. People value gemstones for their color, luster, and durability, and for the fact that they are rare. Once a gemstone is cut and polished, it is called a gem. Gems are used mainly for jewelry and decoration. They are also used for mechanical parts and for grinding and polishing.
Metals Some minerals are the sources of metals such as aluminum, iron, copper, or silver. Metals are generally not as hard as gemstones. But metals are useful because they can be stretched into wire, flattened into sheets, and hammered or molded without breaking. Metal tools and machinery, the metal filament in a light bulb, aluminum foil, and the steel beams used to frame office buildings all began as minerals inside Earth’s crust.
Other Useful Minerals There are many other useful minerals besides metals and gems. People use materials from these minerals in foods, medicines, fertilizers, and building materials. The very soft mineral talc is ground up to make talcum powder. Clear crystals of the mineral calcite are used in optical instruments such as microscopes. Quartz, a mineral found in sand, is used in making glass as well as in electronic equipment and watches. Gypsum, a soft, white mineral, is used to make wallboard, cement, and stucco.
Questions A __________ is a rounded, hollow rock that is often lined with mineral crystals. A. gemstone B. geode C. diamond D. gem
_______________ is the process by which atoms are arranged to form a material with a crystal structure. A. Dissolving B. Evaporation C. Precipitation D. Crystallization
Once a gemstone is cut and polished, it is called a A. ore. B. gold nugget. C. gem. D. All of the above.