Hard Rock Mining Quiz and Flashcards

Study Notes

Hard Rock Mining

Hard rock deposits occur in sedimentary, igneous, and metamorphic rocks, unlike soft rock mining which typically involves coal.
Hard rock mining involves exploring and mining an orebody, which is a mineral that can be exploited safely and at a profit.

Orebody Formation and Classification

Orebody formation processes include weathering and erosion, volcanic processes, sedimentation, and tectonic or metamorphic processes.
Weathering and erosion can break down rocks into minerals, which may become concentrated as either weathering-resistant minerals or in mobile minerals.
Volcanic processes can result in concentrations through crystallization, differential gravity settling, and heat energy.
Sedimentation can result in gravity separation and concentration within clastic sediments.
Tectonic or metamorphic processes can result in the breakdown and transformation of rock minerals and concentration of certain elements.

Types of Orebody Formation

Igneous intrusions include iron, ferro-alloy metals, non-ferrous base metals, precious metals, nuclear elements, magnesite, and barite.
Sedimentary concentration by weathering and/or precipitation includes iron oxides, manganese oxides, bauxite, uranium, and vanadium.
Sea water extraction includes salt and magnesium.
Placer deposits include gold, cassiterite, mercury, zirconium, silica sand, rutile, ilmenite, and monazite.
Pegmatite deposits include feldspar, quartz, rare earth minerals, lithium minerals, and beryllium.
Evaporite deposits include potash, sodium carbonate, sodium sulphate, salt, borax, gypsum, and lithium.
Chemically deposited sedimentary deposits include sulphur, phosphate, strontium minerals, barite, limestone, dolomite, magnesite, and chalk.
Other sedimentary deposits include diatomite, clay, shale, sandstone, quartzite, bentonite, perlite, diamond-bearing rock, and graphite.
Metamorphic deposits include mica, asbestos, talc, vermiculite, pyrophyllite, slate, sillimanites, and magnesite.

Indicators of Mineralization

Rust-colored rocks or soil (Gossan) are a good indication of mineralization, caused by iron, which may indicate the presence of other metallic minerals.
Quartz veins are often associated with sulphide mineral deposits.
Dykes are long thin bodies of igneous rock that may contain or be associated with valuable minerals.
Shear zones are places of weakness or breaks in the earth's crust through which mineralized solutions may have been channelled, and often contain quartz veins.

Description

This quiz covers the basic concepts of hard rock mining, including the geological characteristics of hard rock deposits and the definition of ore. Learn about the differences between soft rock and hard rock mining.