Mineral and Mineral Resources Section 1

What Is a Mineral? A mineral is a naturally occurring, usually inorganic solid that has a characteristic chemical composition, an orderly internal structure, and a characteristic set of physical properties.

Mineral Resources We depend on the use of mineral resources in almost every aspect of our daily life. The current challenge is to obtain the minerals that an ever-increasing world population demands at minimal cost to the environment.

Mineral Consumption per Person (U.S.)

The Top 10 U.S. Mineral Commodities

What Is a Mineral? Native elements, these include the elements gold, silver, and copper. Most minerals are compounds. The mineral quartz is made up of silica, which consists of one silicon atom and two oxygen atoms.

Ore Minerals An ore mineral is a mineral that contains one or more elements of economic value. Ore minerals, are refined using various methods to extract the valuable elements they contain. For mining to be profitable, the price of the final product must be greater than the costs of extraction and refining.

Metallic Minerals Ore minerals are either metallic or nonmetallic. Metals have the following characteristics: can conduct electricity have shiny surfaces are opaque Examples: gold, silver, and copper.

Nonmetallic Minerals Nonmetals have the following characteristics: tend to be good insulators may have shiny or dull surfaces may allow light to pass through

Mineral Environments

Mineral Resources and Their Uses Certain metals are of major economic and industrial importance. Alloys: 2 or more metals combine. Example: zinc, brass

Mineral Resources and Their Uses

Nonmetals are among the most widely used minerals in the world. Gypsum, is used to make building materials such as wallboard and concrete. Gemstones: include diamond, ruby, sapphire, emerald, topaz.

Gypsum

Types of Mining

Subsurface mining Subsurface mining is a mining method in which soil and rocks are removed to reach underlying coal or minerals. Room-and-pillar mining is a common method of subsurface mining. This method is used to extract salt and coal.

Longwall mining is a more efficient method of removing coal from a subsurface seam. A machine called a shearer moves back and forth along the face of a coal seam.

Solution mining is an economical method to mine for deposits of soluble mineral ores, such as potash, salt, and sulfur.

Surface Mining Surface mining is a mining method in which soil and rocks are removed to reach underlying coal or minerals. In open-pit mining, ores are mined downward, layer by layer. coal, gold, and copper are mined with open-pit mining.

Quarrying Quarries are open pit used to mine near-surface materials such as building stone, crushed rock, sand, and gravel. Aggregates, which are sand, gravel, and crushed rock, are produced by quarrying.

Solar Evaporation The solar evaporation process consists of placing sea water into enormous shallow ponds. The sun evaporates the sea water, which causes the sodium chloride concentration to increase. About 30% of the world’s salt comes from the solar evaporation process.

Placer Mining Placer deposits are deposits that contain valuable minerals that have been concentrated by weathered rocks. Stream placers are the most important placers. Streams transport mineral grains to a point where they fall to the streambed and are concentrated.

Smelting Smelting is the melting or fusing of ore in order to separate impurities from pure metal. Flux – materials that bond with impurities and separates from the molten metal.

Undersea Mining The ocean floor contains significant mineral resources, Since the late 1950s, several attempts have been made to mine the ocean,. 2 Reasons why unsuccessful: Competition with land-based companies that can mine minerals more cheaply and the great water depths at which some mineral deposits.

The Environmental Impacts of Mining Mining has a large impact on the environment. Mining industries are heavily regulated in the U.S. There are high costs to preserve the environment. Reclaiming the land, is now a part of every surface mining coal operation.

Air and Noise Pollution Noise is created by equipment and by blasting. Blasting can cause physical damage to nearby structures. Large amounts of dust are produced by all aspects of mining.

Water Contamination Water that seeps through mine sites can pick up or dissolve toxic substances. These contaminants can wash into streams, where they can harm or kill aquatic life. The sulfur in coal reacts with oxygen and water to produce sulfuric acid.

Displacement of Wildlife Removing soil removes all plant life. A good development plan to reclaim a mine site can ensure that the displacement of wildlife is temporary. Dredging a river disturbs river bottoms and destroys aquatic life.

Erosion and Sedimentation Excess rock from mines is sometimes dumped into large piles called dumps. Running water erodes unprotected dumps and transports sediments into nearby streams.

Soil Degradation Soil at a mine site is removed from the uppermost layer downward.

Subsidence Subsidence is the sinking of regions of the ground with little or no horizontal movement.

Underground Mine Fires Fires are a serious environmental consequences of coal mining. Lightning, forest fires, and burning trash can all cause coal-seam fires. Underground fires that burn their way to the surface release smoke and gases that can cause respiratory problems

Mining Regulation and Reclamation Mines are regulated by federal and state laws. Mining companies must comply with the Clean Water Act and the Safe Drinking Water Act, Endangered Species Act.

Reclamation Reclamation is the process of returning land to its original condition after mining is completed. The Surface Mining Control and Reclamation Act of 1977 created a program for the regulation of surface coal mining on public and private land.

State Regulation of Mining Permits from state environmental agencies are required. State agencies inspect mines to ensure compliance with environmental regulations. Agencies issue violations to companies that do not comply with environmental regulations and assess fines for noncompliance.