minerals

what is a mineral?

A mineral is a naturally occurring solid substance with definite chemical and physical properties that forms as a result of geologic processes on Earth.

Soil Profiles

By digging down into soils, you can see how soil formation progresses over time. Soils consist of layers, also known as horizons, which are arranged like layers of a cake. The arrangement of these layers is the soil profile, which characterizes and identifies a particular type of soil. Within the soil profile, each layer has different characteristics.

Metamorphic rocks:

Metamorphic rocks were once sedimentary, igneous, or another metamorphic rock. These rocks are physically deformed and chemically changed due to different temperatures and pressures. The elements in the minerals can actually "move" to form new minerals.

What are five main physical and chemical characteristics that define minerals?

Minerals are solids. Minerals are inorganic Minerals are natural - They are found in the ground. Minerals have a definite crystal structure, meaning the atoms are arranged in a predictable way. Minerals have a definite chemical composition. Pyrite, also known as "fool's gold," has the formula FeS2, meaning each molecule of pyrite is always made up of one iron and two sulfur atoms.

Case Studies

People mine rocks and minerals all over the world. Many of these locations provide case studies on the effects of mining in local environments.

Uses

People use minerals for industry, agriculture, and manufacturing. Industrial processes use large quantities of minerals to create products. Farmers use minerals to help plants grow. For example, they may scatter limestone, which is rich in the mineral calcite, on their fields to neutralize acidic soils. Minerals are also used for decorative purposes. Jewelers prize the crystal forms of many minerals, such as diamonds, for their striking beauty and uniqueness. However, jewelers cannot use all diamonds to make jewelry. Poorer quality diamonds have less value than gem-quality diamonds. But because they are as hard as gem diamonds, they are used in machines to cut other substances. These diamonds are industrial-grade. Other minerals have multiple uses, too. For instance, limestone is also used in the manufacture of cement. You even eat solid chunks of minerals! Common table salt is a mineral, called halite. In fact, in your diet and through your lifestyle, you will use a lot of minerals in your lifetime.

Formation

soils differ in composition, and people use soils in a variety of ways. But what exactly is soil? The soil is a thin layer of material on Earth's crust composed of sediments, gases, moisture, and organic matter. The primary importance of soils is to serve as a medium in which plants can grow. Soils form through the weathering of rocks and minerals. As you learned previously, weathering is the process by which physical and chemical forces break down rocks. Rock material breaks down from the action of water or the wind, as well as human and animal activities and chemical reactions. The cumulative effect of these processes is to break down rock into smaller and smaller pieces. The pieces are then mixed with decaying matter, air, and moisture to form soils. Line graph comparing projected U.S. energy consumption to actual U.S. energy consumption from The types of materials that make up soil are referred to as soil composition. Water and air make up about half the volume of a typical soil. The gases in air sustain microscopic organisms that further break down the rock material. Living organisms in the soil also need water. Water acts as a glue that holds the rock materials together. About 45 percent of the soil is composed of minerals from the parent rock, the primary rock type that forms the soil. Because rock types vary worldwide, so do the types of soils. Finally, about 5 percent of the soil is organic matter from decaying plant and animal material. The more organic matter there is in the soil, the more nutrients the soil will have.

Types of minerals:

Geologists have identified more than 4,000 minerals on Earth. Because minerals are made of elements, some are more common than others, based on the percentages of different elements in Earth's crust. The pie chart below lists the most abundant elements in Earth's crust. Many of the most common minerals on Earth also contain these elements. https://cv-kettle-falls.brainhoney.com/Resource/32015257,DD6,0,0,0,0/Assets/Earth_Space_Science_v12_GS/rocksminerals/images/rm_01b_b_03.gif

The Rock Cycle

A particular rock may not always remain the same type. Igneous, metamorphic, and sedimentary rocks are transformed as they pass through the rock cycle. The rock cycle is the continuous transformation of rocks from one type to another within the geosphere. All rocks on Earth started as igneous rocks, approximately 4.6 billion years ago. Over time, forces from wind, water, heat, and pressure transformed these early rocks into sedimentary and metamorphic rocks. Despite its name, the rock cycle is not a loop. Rocks can change from one form to another and back again. A better term would be the rock "recycle," because rocks are continuously recycled on Earth. According to the Law of Conservation of Matter, rocks and other materials are neither created nor destroyed. Instead, materials change form. Use the following activity to investigate the pathways of the rock cycle. Be sure to take notes on the ways rocks can transform from one type into another. You will use this information again later.

What are minerals composed of?

All minerals are composed of one or more elements from the periodic table.

distribution

As you have learned, minerals are an abundant and important resource used in a variety of ways. The mineral resources on Earth have been in existence since the beginning of Earth's history (though if people do not use mineral resources carefully, they may not last long into the future). Scientists continue to study the various forms of minerals in an effort to better understand Earth, its history, and its future.

What characteristics does it take to be a mineral?

Be a single pure substance Be a naturally occurring solid Be formed by inorganic processes Have a crystalline structure Have specific chemical composition

Climate

Climate is important in determining the types of soils that form, because an area's climate dictates the predominant weather patterns. For instance, in cold, arctic regions where there is less plant life, the layer of organic material is usually thin. In tropical regions, heavy precipitation leaches the soil's nutrients down into deeper layers.

Soil Characteristics

Different soils form under different conditions, leading to differing characteristics. These varying features give clues to how the soils are formed collecting a soil sample is not as simple as going outside and scraping a few teaspoons of dirt into a jar. A soil sample, properly collected, can be used to examine the properties and composition of that particular soil. By collecting several samples from the same area, you will have a good survey of the different soils in that area. When collecting a soil sample, notice that some soils are much harder than others. The way a soil is compacted can tell you how much air and moisture there is in the soil. Some soils are very loose, like sand, while others are very hard, almost rocklike. Soils also have different colors. Soil color can tell you a lot about how a soil formed. Even in your own backyard, you could dig at various locations and probably find several different soil colors. Soil colors vary with depth. Soil color also varies by location and mineral content. A soil color chart, such as the Munsell chart you saw in the video, can help you identify soil characteristics.

Distribution

Economists consider minerals to be nonrenewable resources. A nonrenewable resource is one that, once used up, cannot be easily replaced. The distribution of specific minerals across the globe is uneven. Some minerals that may be abundant in some areas may be absent in others. That means that not all minerals are readily available to all areas.

Mining operation

Geologists must first determine if the mineral ore is of high enough quality and in sufficient quantity to make mining profitable. The mining company must purchase heavy machinery for extracting and removing the rock. The company must also hire a labor force and train the workers as needed to handle specialized tasks in the mine. Once removed, the rock may still need to go through several more rounds of processing to become usable by manufacturers. Once the mining company has removed the minerals, land areas that have been mined must go through reclamation, depending on regional laws governing mining operations. Reclamation returns the land to a usable state after mining operations have ceased. There are advantages and disadvantages to consider when mining material. Review the lists of pros and cons. Can you think of any others? Pros: Creates jobs Extracts important rocks and minerals for human use Cons: Disrupts the local ecosystem Disrupts the local water cycle; runoff can be contaminated, and sediment can fill in rivers and streams Working conditions in the mine can be dangerous

Igneous Rocks:

Igneous rock is formed through the cooling and solidification of magma or lava. Igneous rock may form with or without crystallization, either below the surface as intrusive (plutonic) rocks or on the surface as extrusive (volcanic) rocks.

minerals form as a result of what four basic, natural processes?

Minerals form as magma and lava cools. This process is known as crystallization. The chemical elements within the magma or lava combine in specific ratios to form mineral crystals of various forms. Minerals form in water as precipitates. A precipitate is an insoluble solid that separates from a liquid solution. Also, when chemical elements dissolve in hot water, they form a solution. When the water evaporates, it leaves solid minerals behind. Weathering is the process by which minerals on Earth are broken down over time. Minerals can be weathered by physical and chemical methods such as wind, weather, water and ice and can transform them into new minerals. Changes in pressure deep beneath Earth's surface also cause minerals to form. As the pressure increases, minerals combine to become new minerals. Extreme heat has the same effect on minerals

Fossil fuels

Mining also refers to the extraction of fossil fuels from Earth. Fossil fuels form as once-living things decompose over millions of years. Oil, coal, and natural gas are fossil fuels.

Mining

Mining is the process by which people extract rocks and minerals from the ground and process them into usable resources.

Are oil and coal minerals?

No, because they do not meet the five rule criteria.

Not all rocks are pure minerals.

Not all rocks are pure minerals. That is because minerals are the building blocks of all rocks. As you learned in the previous lesson, a rock is a natural, non-living, solid substance containing one or more minerals. All rocks contain minerals, and so rocks share some of the characteristics of the individual minerals that make them up.

texture sand silt clay

One of a soil's most important characteristics is the size of its mineral grains. This characteristic is the soil texture. To feel the texture of the soil, roll a sample of it between your fingers. There are three basic soil textures, each based on particle size. If you measure the sizes of individual grains in the soil, you typically find a wide range of particle sizes.

Sedimentary Rocks:

Processes in the hydrosphere, atmosphere, geosphere, cryosphere, and biosphere constantly erode rocks above and below Earth's surface. These processes break down rocks. The breakdown of rocks by physical and chemical means is called weathering. Weathered rock can exist in solution or as particulate matter suspended in water, collectively known as sediments. When water and other forces move sediments to new locations, the relocated material may be deposited as sedimentary rock. The process of lithification occurs when loose sediment compresses to form solid sedimentary rock. Most sedimentary rocks are made up of small or large pieces of other rocks that are cemented together. Nearly all fossils are found in sedimentary rocks. Sedimentary rocks may also contain layers of different types of sediment.

Reclamation

Reclamation is the process of putting land back to the same, or nearly the same, state it was in before the mining began

resorces & controversy

Rock and mineral resources sometimes cause controversy. One example is the so-called coltan crisis in Africa. Coltan is a combination of several minerals important to industry. Competition for these minerals has caused armed conflict in the Democratic Republic of the Congo, shown in the map above, and so trade in coltan is very controversial: On the one hand, it invites conflict, but on the other, it is an essential component of many household products.

Rocks Vs Minerals Matching—Answers

Rocks made of one or more minerals granite sandstone Minerals diamonds chemical composition always the same Both solid nonliving naturally occurring made of elements and compounds

Synthetic minerals:

Scientists have been able to successfully re-create minerals in a laboratory setting. Some of these synthetic—or lab-created—minerals, such as rubies and emeralds, look very much like the minerals found in nature. Other minerals are created in the lab because the real minerals are either too expensive or rare to extract from the ground.

classifying rocks you must observe their properties visually or by appropriate testing.

Size Shape Composition Color Use or Purpose

Did you know?

Some minerals are a mystery. In Mexico, Cueva de Los Cristales (Cave of the Crystals) contains some of the largest mineral crystals ever found. You can view them at the Storm Chaser site. Scientists were at first puzzled when the giant gypsum crystals, measuring up to 36 feet long, were discovered in 2000. After careful studies, it was found that mineral-rich water at constant high temperatures had filled the caves, allowing the crystals to grow to these large sizes. The caves had then drained, leaving humans to discover the immense crystals. Mystery solved!

Geologists use different tools to help them identify minerals:

Streak plate: A mineral is rubbed across a white or black ceramic streak plate. The surface of the streak plate causes some of the mineral to become a powdered "streak" of the mineral. Geologists then determine the color of the mineral in its powdered form, which may differ from the overall color of the solid mineral. Hardness points: The hardness of a mineral is its resistance to scratching on a scale of 1 to 10. Diamonds and corundum are minerals that are very hard. Talc and gypsum are minerals that are very soft. Magnet: Some minerals contain metals and can be magnetized. Other minerals are natural magnets. Acids: Some minerals contain substances that cause them to react with acids. Geologists use such reactions to identify the mineral. Specific gravity apparatus: Geologists use a specific gravity cup to measure a mineral's density. Specific gravity compares the density of water (used as a standard) to the density of the mineral. Goniometer: A goniometer is used to measure the size and angles of mineral crystals. Most minerals form crystals. Depending on the mineral, its specific crystal shape will be one of six basic types. Crystals need room to grow. If there is no room, or if the mineral forms too quickly, a crystal shape may not be visible. Hammer: A geologist uses a hammer to split a mineral sample into smaller parts. Minerals will usually split in regular, flat ways based on the internal arrangement of atoms within the mineral. This splitting is known as cleavage. Some minerals fracture, which means the mineral breaks, but not in the same flat planes that result from cleavage. Eyes: A geologist uses other tests to determine a mineral's color, shininess, and shape. The way that light shines on a mineral is known as luster. The luster of a mineral may be dull, glassy, shiny, metallic (looks like a metal), nonmetallic (does not look like a metal), or more. The geologist may also collect data on where the mineral was found and how it may have formed.

Which products do you use that contain minerals?

Talcum powder Furniture Cell phones Cereal Jewelry MP3 player Lightbulbs

Effects of Mining

Uranium Mining in the Southwest: Since the 1920s, businesses have conducted uranium mining in the Southwestern United States, on land that has historically been part of the Navajo Nation. Extracting the uranium exposed many workers to dangerous levels of radiation. Although the mines are now closed, the radiation persists and will remain for thousands of years. Limestone Mining in Florida: Florida ranks as the second largest producer of crushed limestone in the United States. The stone is used primarily in road construction; processed limestone is an important component of cement. Problems associated with mining limestone include large holes left in the ground, loud blasts from the explosives frequently used while mining, and potential pollution of surface and groundwater supplies in the state. Phosphate Mining in Nauru: Phosphates, often used as a fertilizer ingredient, have been mined from the South Pacific island of Nauru since the early 20th century. As a result, deep pits and stacks of leftover rock have devastated the island. Today the native population can no longer live on four-fifths of the island's land area.

The essential minerals your body needs are different than geologic minerals.

Your body extracts mineral elements, such as calcium, from plant or animal food to sustain your body's living processes. The mineral elements your body needs get into the soil as a result of the presence and gradually breakdown of geologic minerals. For instance, limestone is a form of calcium carbonate present in soils. As it breaks down over time, it leaves behind calcium that your body can use to grow and stay healthy.