|
Ore Real
Ore is natural Rock (geology), rock or sediment that contains one or more valuable minerals, typically containing metals, that can be mined, treated and sold at a profit.Encyclopædia Britannica. "Ore". Encyclopædia Britannica Online. Retrieved 7 April 2021Neuendorf, K.K.E., Mehl, J.P., Jr., and Jackson, J.A., eds., 2011, Glossary of Geology: American Geological Institute, 799 p. Ore is extracted from the earth through mining and treated or Refining (metallurgy), refined, often via smelting, to extract the valuable metals or minerals. The ''grade'' of ore refers to the concentration of the desired material it contains. The value of the metals or minerals a rock contains must be weighed against the cost of extraction to determine whether it is of sufficiently high grade to be worth mining, and is therefore considered an ore. Minerals of interest are generally Oxide mineral, oxides, Sulfide mineral, sulfides, silicate minerals, silicates, or native metals such as native copp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Banded Iron Formation
Banded iron formations (also known as banded ironstone formations or BIFs) are distinctive units of sedimentary rock consisting of alternating layers of iron oxides and iron-poor chert. They can be up to several hundred meters in thickness and extend laterally for several hundred kilometers. Almost all of these formations are of Precambrian age and are thought to record the oxygenation of the Earth's oceans. Some of the Earth's oldest rock formations, which formed about ( Ma), are associated with banded iron formations. Banded iron formations are thought to have formed in sea water as the result of oxygen production by photosynthetic cyanobacteria. The oxygen combined with dissolved iron in Earth's oceans to form insoluble iron oxides, which precipitated out, forming a thin layer on the ocean floor. Each band is similar to a varve, resulting from cyclic variations in oxygen production. Banded iron formations were first discovered in northern Michigan in 1844. Band ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
