Concept
Ore
Related concepts (75)
Fluid inclusion
A fluid inclusion is a microscopic bubble of liquid and/or gas that is trapped within a crystal. As minerals often form from a liquid or aqueous medium, tiny bubbles of that liquid can become trapped within the crystal, or along healed crystal fractures. These small inclusions range in size from 0.01 mm to 1 mm and are usually only visible in detail by microscopic study. These inclusions occur in a wide variety of environments.
Magnetic separation
Magnetic separation is the process of separating components of mixtures by using a magnet to attract magnetic substances. The process that is used for magnetic separation separates non-magnetic substances from those which are magnetic. This technique is useful for the select few minerals which are ferromagnetic (iron-, nickel-, and cobalt-containing minerals) and paramagnetic. Most metals, including gold, silver and aluminum, are nonmagnetic. A large diversity of mechanical means are used to separate magnetic materials.
National Museum of Natural History
The National Museum of Natural History is a natural history museum administered by the Smithsonian Institution, located on the National Mall in Washington, D.C., United States. It has free admission and is open 364 days a year. In 2022, with 3.9 million visitors, it was the most-visited museum in the United States. Opened in 1910, the museum on the National Mall was one of the first Smithsonian buildings constructed exclusively to hold the national collections and research facilities.
Polymetal
In chemistry or mining, polymetal or polymetallic is a substance composed of a combination of different metals. When the substance contains only two metals the term bimetal (bimetallic) is sometimes preferred. A (or ) is an ore that is the source of more than one metal suitable for recovery. A mine containing polymetallic ore is a . Concretions of manganese and iron (and other metals) found on the ocean floor are called s. They are sometimes called manganese nodules, after their principal component.
Underground soft-rock mining
Underground soft-rock mining is a group of underground mining techniques used to extract coal, oil shale, potash, and other minerals or geological materials from sedimentary ("soft") rocks. Because deposits in sedimentary rocks are commonly layered and relatively less hard, the mining methods used differ from those used to mine deposits in igneous or metamorphic rocks (see underground hard-rock mining). Underground mining techniques also differ greatly from those of surface mining.