The Use of Minerals. Chapter 3

Transcription

1 Section 3 The Formation, Mining, and Use of Minerals The Use of Minerals Metallic Minerals are good conductors of heat and electricity. They can be processed for various uses, including building aircraft, automobiles, and communications and electronic equipment. Examples of useful metallic minerals include gold, silver, and copper.

2 Section 3 The Formation, Mining, and Use of Minerals Nonmetallic Minerals are good insulators of electricity. They have uses that range from glass-making to producing computer chips. Calcite, one nonmetallic mineral, is a major component of concrete, which is used in building roads, buildings, bridges and other structures.

3 Section 3 The Formation, Mining, and Use of Minerals Gemstones are highly valued for their beauty and rarity, than for their usefulness. Important gemstones include diamond, sapphire, ruby, emerald, aquamarine, topaz, and tourmaline.

4 Section 1 What Is a Mineral? Key Points Notes Mineral Structure Hi, Mrs. Parsons class! My name is Ruby Redding. I ll be helping you take notes.

5 Section 1 What Is a Mineral? Mineral Structure A mineral is a naturally formed, inorganic solid that has a definite crystalline structure. You can ask 4 questions to determine if an object is a mineral!

6 Section 1 What Is a Mineral? Is it a nonliving material? Is it a solid? Does it have a crystalline structure? Is it formed in nature?

7 Section 1 What Is a Mineral? Let s practice! Is coal a mineral? Is salt a mineral? Is sugar a mineral?

8 Section 1 What Is a Mineral? Elements are pure substances that cannot be separated or broken down into simpler substances by chemical means. To understand what a crystalline structure is, you need to know about the atoms that make up a minerals.

9 Section 1 What Is a Mineral? Solid, geometric forms of minerals produced by a repeating pattern of atoms that is present throughout the mineral are called crystals. A crystal s shape is determined by the arrangement of the atoms within the crystal. The arrangement of atoms in turn is determined by the kinds of atoms that make up the mineral.

10 Section 1 What Is a Mineral? What does it look like when crystals form into a mineral?

11 Section 1 What Is a Mineral? Let s make minerals and take a look at their crystalline structures

12 Section 1 What Is a Mineral? Two Groups of Minerals Minerals are divided into two groups based on their chemical composition. Silicate minerals are minerals that contain a combination of silicon, oxygen, and one or more metals. Examples of silicate minerals are quartz, feldspar, and mica.

13 Section 1 What Is a Mineral? Two Groups of Minerals, continued Nonsilicate minerals are minerals that do not contain compounds of silicon and oxygen. There are six main classes of nonsilicate minerals. Native Elements Carbonates Halides Oxides Sulfates Sulfides

14 Section 1 What Is a Mineral? Key Points Notes Mineral Structure Silcates/ nonsilicate Seven ways to identify minerals Make sure to keep notes with their key points!

15 Section 2 Identifying Minerals Identifying Minerals You can determine the identity of a mineral by noting different properties. Color Minerals display a wide variety of colors, and often the same mineral can be found in many different colors. Because of this, color is usually not the best way to identify a mineral.

16 Section 2 Identifying Minerals The way a mineral reflects light is called luster. There are three types of mineral luster: Metallic Submetallic Nonmetallic

17 Section 2 Identifying Minerals The color of a mineral in powdered form is called the mineral s streak. A mineral s streak can be found by running the mineral against a piece of unglazed porcelain called a streak plate. The color of a mineral s streak is not always the same as the color of the mineral sample.

18 Section 2 Identifying Minerals Mineral Color, Luster, and Streak Click below to watch the Visual Concept. Visual Concept

19 Section 2 Identifying Minerals Cleavage and Fracture Different types of minerals break in different ways. Cleavage is the tendency of some minerals to break along smooth, flat surfaces. Fracture is the tendency of some minerals to break unevenly along curved or irregular surfaces.

20 Section 2 Identifying Minerals Hardness A mineral s resistance to being scratched is called hardness. To determine the hardness of minerals, scientists use Mohs hardness scale, shown on the next slide.

21 Section 2 Identifying Minerals

22 Section 2 Identifying Minerals Density Density is the measure of how much matter is in a given amount of space. Density is a ratio of an object s mass to its volume. Different minerals have different densities.

23 Section 2 Identifying Minerals Special Properties Some properties are particular to only a few types of minerals. The properties shown on the next slide can help you quickly identify some minerals.

24 Section 2 Identifying Minerals

25 Section 3 The Formation, Mining, and Use of Minerals Activity Look at a mineral resource map of your state and locate the mines closest to where you live. Which mineral commodities are mined there?

26 Section 3 The Formation, Mining, and Use of Minerals Formation of Minerals Minerals form in a variety of environments in the Earth s crust. Each environment has a different set of physical and chemical conditions that determine the minerals properties. 1) Evaporating Salt Water When a body of salt water dries up, minerals such as gypsum and halite are left behind.

27 Section 3 The Formation, Mining, and Use of Minerals 2) Metamorphic Rocks When changes in pressure, temperature, or chemical makeup alter a rock, metamorphism takes place. Minerals that form in metamorphic rock include calcite, garnet, graphite, hematite, magnetite, mica, and talc.

28 Section 3 The Formation, Mining, and Use of Minerals 3) Limestones Surface water and groundwater carry dissolved materials into lakes and seas, where they crystallized on the bottom. Minerals that form in this environment include calcite and dolomite.

29 Section 3 The Formation, Mining, and Use of Minerals 4) Hot-Water Solutions Groundwater works its way downward and is heated by magma, and then reacts with minerals to form a hot liquid solution. Dissolved metals and other elements crystallize out of the hot fluid to form new minerals, such as gold, copper, sulfur, pyrite, and galena.

30 Section 3 The Formation, Mining, and Use of Minerals 5) Pegmatites As magma rises upward from the Earth s crust, it can form teardrop-shaped bodies called pegmatites. Many gemstones such as topaz and tourmaline, form in pegmatites.

31 Section 3 The Formation, Mining, and Use of Minerals 6) Plutons As magma rises upward through the crust, it sometimes stops moving before it reaches the surface and cools slowly, forming millions of mineral crystals. Eventually, the entire magma body solidifies, forming minerals such as mica, feldspar, magnetite, and quartz.

32 Section 3 The Formation, Mining, and Use of Minerals Mining Many kinds of rocks and minerals must be mined to extract the valuable elements they contain. Geologists use the term ore to describe a mineral deposit large enough and pure enough to be mined for profit.