Understanding Minerals: Formation, Properties, and Uses

1. Warm Up • Draw a picture of what you think the inside of the earth looks like. • Put a star where you think you would find minerals. • Write whether you agree or disagree with the following statements. • A mineral is anything solid on Earth. • The best way to identify a mineral is by color. • Hardness, streak, and luster are among the properties used to identify minerals

2. Objectives • SWBAT define mineral. • SWBAT explain how a mineral forms. • SWBAT list how mineral are categorized.

3. What are minerals and why are they useful? Chapter Introduction

4. What is a mineral? • What is a mineral? • What are the common rock-forming minerals? • How do minerals form? Lesson 1 Reading Guide - KC

5. What is a mineral? • Mineral • crystallization • Magma • cleavage • fracture • density • luster • streak • hardness Lesson 1 Reading Guide - Vocab

6. What is a mineral? • A mineral is a naturally occurring, inorganic solid with a definite chemical composition and an orderly arrangement of atoms or ions. • There are approximately 4,000 minerals on Earth, but only about 30 are common. Lesson 1-1

7. What is a mineral?(cont.) What is a mineral? Lesson 1-1

8. What is a mineral?(cont.) • Minerals have a definite chemical composition. • Always contains certain elements in the same proportion. • Some minerals, such as silver and sulfur, are composed of just one element. • But, most minerals are compounds, (two or more different elements chemically joined). Lesson 1-1

9. What is a mineral?(cont.) • Minerals form predictable crystal patterns. • particles line up in a regular, repeating pattern. • flat sides called faces, that meet at sharp edges and corners. Lesson 1-1

10. What is a mineral?(cont.) A crystal is a solid with a repeating arrangement of atoms or ions in 3 directions. Lesson 1-1

11. What is a mineral?(cont.) • Minerals are solids, meaning they have an orderly internal arrangement of atoms or ions. • Minerals are inorganic, or they are naturally occurring made from non-living things • Despite being inorganic, some minerals can form as a result of organic processes. Lesson 1-1

12. The Structure of Minerals • Minerals occur in many different shapes. • When a crystal forms under the right conditions and has time to grow, it will develop a characteristic crystal shape. • Most of the time, minerals grow in tiny clusters. Lesson 1-2

13. The Structure of Minerals(cont.) • The common rock-forming minerals are composed of combinations of elements that are abundant in Earth’s crust. • Oxygen and silicon are the two most plentiful elements in the crust. Lesson 1-2

14. How do minerals form? • All minerals form through crystallization. • The process of crystallization occurs when particles dissolved in a liquid or a melt solidify and form crystals. • The chemical and physical properties of minerals can help geologists infer the type of environment where these minerals formed. Lesson 1-3

15. How do minerals form?(cont.) • Minerals can also form from magma. Magmais molten material stored beneath Earth’s surface. • When magma erupts on or near Earth’s surface, it is called lava or ash. lava from Latin lavare, means “to wash” Lesson 1-3

16. How do minerals form?(cont.) • As lava or ash cools above ground or magma cools underground, atoms and ions arrange themselves and form mineral crystals. • Small crystals form as lava cools quickly on or near Earth’s surface and large crystals sometimes form as magma cools and crystallizes slowly below Earth’s surface. Lesson 1-3

17. How do minerals form?(cont.) • Minerals that form deep within Earth’s crust and mantle are stable under high pressure and high temperature conditions. • Metamorphic activity can uplift minerals from great depths onto Earth’s surface. • Changes in pressure and temperature on Earth’s surface combined with agents of erosion can cause minerals to break down and eventually form new minerals. Lesson 1-3

18. Put a star next to the information that is most important on your notes sheet. • Use the objectives.

19. Physical Properties • Color alone cannot be used for mineral identification because many different minerals can be the same color. Lesson 2-1

20. Luster The way a mineral reflects light. Can be metallic or non-metallic. Shiny or dull. waxy, pearly, glassy. Physical Properties(cont.) This is a gem stone called tourmaline it has a glassy luster

21. Streak The color of its powder. Not always the same as the color of the mineral. Streak is only useful for identifying minerals that are softer than porcelain. Nonmetallic minerals generally produce a white streak. http://geology.csupomona.edu/alert/mineral/streak.htm Properties of Minerals

22. Hardness A measure of how easily a mineral can be scratched. Physical Properties(cont.) http://www.info-diamond.co.uk Properties of Minerals

23. Physical Properties(cont.) • Friedrich Mohs developed the Mohs’ hardness scale to compare the hardness of different minerals, with scale ranging from 1 to 10. Lesson 2-1

24. Lesson 2-1

25. Physical Properties(cont.) • Sometimes the way a mineral breaks provides clues to its identity. • The arrangement of atoms or ions and the strengths of their chemical bonds determine how a mineral breaks. • Minerals break where bonds between atoms or ions are weak. Lesson 2-1

26. Density Minerals will have a certain density regardless of the size of the sample. http://www.astronomynotes.com/cosmolgy/ Properties of Minerals

27. Physical Properties(cont.) • If a mineral breaks with smooth, flat surfaces, it has cleavage. • If a mineral breaks and forms uneven surfaces, it has fracture. cleavage from Old English cleofan, means “to split, separate” Lesson 2-1

28. Color first thing noticed about minerals Some minerals have special properties, such as texture, odor, fluorescence, magnetism, or the way they react when they come in contact with hydrochloric acid. http://www.nmnh.si.edu/rtp/students/2004/virtualposters/poster Properties of Minerals

29. Wrap Up • Identify all the properties used to classify an unknown mineral. • How are minerals formed? Lesson 2-1