Search results
Results from the WOW.Com Content Network
Ore minerals in IOCG deposits are typically copper-iron sulfide chalcopyrite and gangue pyrite, forming 10–15% of the rock mass. Supergene profiles can be developed above weathered examples of IOCG deposits, as exemplified by the Sossego deposit, Para State, Brazil , where typical oxidised copper minerals are present, e.g.; malachite ...
Platinum is an extremely rare metal, [26] occurring at a concentration of only 0.005 ppm in Earth's crust. [ 27 ] [ 28 ] Sometimes mistaken for silver, platinum is often found chemically uncombined as native platinum and as alloy with the other platinum-group metals and iron mostly.
A rare but notable gamma source is sodium-24; this has a fairly short half-life of 15 hours, but it emits photons with very high energies (>2 MeV). It could be used for radiography of thick steel objects if the radiography occurred close to the point of production.
Primary cobalt deposits are rare, such as those occurring in hydrothermal deposits, associated with ultramafic rocks, typified by the Bou-Azzer district of Morocco. At such locations, cobalt ores are mined exclusively, albeit at a lower concentration, and thus require more downstream processing for cobalt extraction. [93] [94]
This is a list of printed books, manuscripts, letters, music scores, comic books, maps and other documents which have been sold for more than US$1 million. The dates of composition of the books range from the 7th-century Quran leaf palimpsest and the early 8th-century St Cuthbert Gospel , to a 21st-century autograph manuscript of J. K. Rowling ...
Like the halogens of rare earth elements, actinide chlorides, bromides, and iodides are water-soluble, and fluorides are insoluble. Uranium easily yields a colorless hexafluoride, which sublimates at a temperature of 56.5 °C; because of its volatility, it is used in the separation of uranium isotopes with gas centrifuge or gaseous diffusion .
Carter County is a county in the Ozarks of Missouri.At the 2020 census, it had a population of 5,202. [1] The largest city and county seat is Van Buren. [2] The county was officially organized on March 10, 1859, and is named after Zimri A. Carter, a pioneer settler who came to Missouri from South Carolina in 1812.
The internal structure of Earth. In geology, the crust is the outermost solid shell of a planet, dwarf planet, or natural satellite.It is usually distinguished from the underlying mantle by its chemical makeup; however, in the case of icy satellites, it may be defined based on its phase (solid crust vs. liquid mantle).