Ferroselite
Encyclopedia
Ferroselite is an iron
selenide
of general formula FeSe2 precipitated under reducing conditions in anoxic environments. It is a source of selenium in the Rocky Mountains where selenium occurrence is associated with Upper Cretaceous shale deposits.
It was first reported in 1955 for an occurrence in the Ust’-Uyuk uranium deposit in Tuva
, Siberia
.
In the frame of safety assessment calculations made for deep disposal of high-level radioactive waste, ferroselite (and its polymorph dzharkenite) is also considered in geochemical calculations as one of the mineral phases limiting the solubility of Selenium-79
.
Iron
Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...
selenide
Selenide
A selenide is a chemical compound in which selenium serves as an anion with oxidation number of −2 , much as sulfur does in a sulfide. The chemistry of the selenides and sulfides are similar....
of general formula FeSe2 precipitated under reducing conditions in anoxic environments. It is a source of selenium in the Rocky Mountains where selenium occurrence is associated with Upper Cretaceous shale deposits.
It was first reported in 1955 for an occurrence in the Ust’-Uyuk uranium deposit in Tuva
Tuva
The Tyva Republic , or Tuva , is a federal subject of Russia . It lies in the geographical center of Asia, in southern Siberia. The republic borders with the Altai Republic, the Republic of Khakassia, Krasnoyarsk Krai, Irkutsk Oblast, and the Republic of Buryatia in Russia and with Mongolia to the...
, Siberia
Siberia
Siberia is an extensive region constituting almost all of Northern Asia. Comprising the central and eastern portion of the Russian Federation, it was part of the Soviet Union from its beginning, as its predecessor states, the Tsardom of Russia and the Russian Empire, conquered it during the 16th...
.
In the frame of safety assessment calculations made for deep disposal of high-level radioactive waste, ferroselite (and its polymorph dzharkenite) is also considered in geochemical calculations as one of the mineral phases limiting the solubility of Selenium-79
Selenium-79
Selenium-79 is a radioisotope of selenium present in spent nuclear fuel and the wastes resulting from reprocessing this fuel. It is one of only 7 long-lived fission products. Its yield is low as it is near the lower end of the mass range for fission products...
.
See also
- Dzharkenite, also of FeSe2 formula, a polymorph of ferroselite
- Coccolithophorid, a group of marine planktonic unicellular algae fixing selenium in Upper Cretaceous chalk and shale formations
- Emiliania huxleyiEmiliania huxleyiEmiliania huxleyi, often abbreviated "EHUX", is a species of coccolithophore with a global distribution from the tropics to subarctic waters. It is one of thousands of different photosynthetic plankton that freely drift in the euphotic zone of the ocean, forming the basis of virtually all marine...
, a major species of coccolithophorid active in selenium bioconcentration