Mineral Resources: Origin

Summary

This video delves into the fascinating world of mineral resources, categorizing them into metallic and non-metallic types. It explores how mineral deposits form, with a focus on processes like magmatic, hydrothermal, sedimentary, placer, and residual ore formation. The video explains the economic factors behind mining, including concentration factors, and how minerals are processed to extract valuable substances. It also covers various types of ore deposits, such as those found in igneous rocks, oceanic spreading centers, and sedimentary basins, making it a comprehensive overview of the complexities in mining and resource extraction.

Takeaways

• 😀 Mineral resources are divided into two categories: metallic (e.g., gold, silver) and non-metallic (e.g., sand, sulfur).
• 😀 A mineral resource is a volume of rock enriched in one or more useful materials, such as salt, gemstone, or sand.
• 😀 Extraction costs vary based on the mineral and its concentration; higher concentrations are more economical to mine.
• 😀 Ore is a body of material from which one or more valuable substances can be extracted economically.
• 😀 Gang minerals are waste minerals in ore deposits that do not contain valuable substances.
• 😀 The concentration factor determines the necessary concentration of a mineral in a deposit to be profitable for mining.
• 😀 Mineral deposits can be classified by the mechanism responsible for concentrating valuable substances, with five origins: magmatic, hydrothermal, sedimentary, placer, and residual.
• 😀 Magmatic ore deposits form by processes like crystal fractionation, where heavier minerals concentrate at the bottom of the magma chamber.
• 😀 Hydrothermal ore deposits occur when hot water circulating through fractures precipitates valuable minerals as it cools.
• 😀 Sedimentary ore deposits are formed by chemical precipitation from lake or sea water, and examples include evaporite deposits and iron formations.
• 😀 Placer deposits are formed by gravity separation during sedimentary processes, concentrating heavy minerals like gold, platinum, and tin.
• 😀 Residual ore deposits result from chemical weathering, with minerals like bauxite and nickel laterites forming from the leaching of rocks in tropical climates.

Q & A

What are the two major categories of mineral resources?

Mineral resources can be divided into two major categories: metallic resources (such as gold, silver, tin, and copper) and non-metallic resources (such as sand, talc, fluorite, and sulfur).

What is a mineral resource?

A mineral resource is a volume of rock enriched in one or more useful materials. The term 'mineral' can refer to any substance derived from the Earth, such as sand, salt, or gemstones.

How is iron extracted from its minerals?

Iron is found in abundance in minerals, but the extraction process varies depending on the mineral. For example, hematite, an oxide mineral, is easier to extract from, whereas minerals like pyroxene contain less iron and require more energy for extraction.

What is the concentration factor in mineral deposits?

The concentration factor is the ratio of the economical concentration of a substance to its average crustal abundance. This helps determine how much of a mineral needs to be present in a deposit for mining to be profitable.

What are gang minerals?

Gang minerals are minerals that occur in a deposit but do not contain valuable substances. They are essentially waste materials in the mining process.

What are magmatic ore deposits?

Magmatic ore deposits are formed by the concentration of substances within a body of igneous rock through magmatic processes such as crystal fractionation and crystal setting.

What are hydrothermal ore deposits?

Hydrothermal ore deposits form when hot aqueous fluids move through fractures and pore spaces in rocks, dissolving valuable substances. As these fluids cool, the dissolved substances precipitate out, forming concentrated deposits.

How do sedimentary ore deposits form?

Sedimentary ore deposits form through chemical precipitation from lake or sea water. For example, evaporite deposits occur in closed marine environments where evaporation is greater than water inflow, leading to the concentration and precipitation of minerals.

What are placer ore deposits?

Placer ore deposits are formed by the concentration of valuable substances through gravity separation during sedimentary processes. This usually happens in streams or along coastlines where heavy minerals like gold, platinum, and diamonds are concentrated by flowing water.

What is the process of secondary enrichment in mineral deposits?

Secondary enrichment occurs when a mineral deposit undergoes weathering, which concentrates the valuable substances in the deposit. This can make an existing mineral deposit more concentrated and economically viable.