Third stream elements are Be-7,Nitrogen, Silicon, Iron(Nickel) and Cadmium(Barium) in elemental periodic table.

Occurrence on Earth of LithiumEdit

Lithium is widely distributed on Earth but does not naturally occur in elemental form due to its high reactivity.[1] Estimates for crustal content range from 20 to 70 ppm by weight.[2] In keeping with its name, lithium forms a minor part of igneous rocks, with the largest concentrations in granites. Granitic pegmatites also provide the greatest abundance of lithium-containing minerals, with spodumene and petalite being the most commercially viable sources.[2] A newer source for lithium is hectorite clay, the only active development of which is through the Western Lithium Corporation in the United States.[3]

According to the Handbook of Lithium and Natural Calcium, "Lithium is a comparatively rare element, although it is found in many rocks and some brines, but always in very low concentrations. There are a fairly large number of both lithium mineral and brine deposits but only comparatively a few of them are of actual or potential commercial value. Many are very small, others are too low in grade."[4] At 20 mg lithium per kg of Earth's crust [5], lithium is the 25th most abundant element. Nickel and lead have the about the same abundance.

The largest reserve base of lithium is in the Salar de Uyuni area of Bolivia, which has 5.4 million tons. According to the US Geological Survey, the production and reserves of lithium in metric tons are as follows[6][7]:

Contrary to the USGS data in the table, other estimates put Chile's reserve base at 7,520,000 metric tons of lithium, and Argentina's at 6,000,000 metric tons.[8]

Seawater contains an estimated 230 billion tons of lithium, though at a low concentration of 0.1 to 0.2 ppm.[9]

Occurrence of NitrogenEdit

Nitrogen is the largest single constituent of the Earth's atmosphere (78.082% by volume of dry air, 75.3% by weight in dry air). It is created by fusion processes in stars, and is estimated to be the 7th most abundant chemical element by mass in the universe.[10]<! The abundance of Neon is very similar and some books quote Neon as 7th and nitrogen 8th.->

Molecular nitrogen and nitrogen compounds have been detected in interstellar space by astronomers using the Far Ultraviolet Spectroscopic Explorer.[11] Molecular nitrogen is a major constituent of the Saturnian moon Titan's thick atmosphere, and occurs in trace amounts in other planetary atmospheres.[12]

Nitrogen is present in all living organisms, in proteins, nucleic acids and other molecules. It typically makes up around 4% of the dry weight of plant matter, and around 3% of the weight of the human body. It is a large component of animal waste (for example, guano), usually in the form of urea, uric acid, ammonium compounds and derivatives of these nitrogenous products, which are essential nutrients for all plants that are unable to fix atmospheric nitrogen.

Nitrogen occurs naturally in a number of minerals, such as saltpetre (potassium nitrate), Chile saltpetre (sodium nitrate) and sal ammoniac (ammonium chloride). Most of these are relatively uncommon, partly because of the minerals' ready solubility in water. See also Nitrate minerals and Ammonium minerals.

Occurrence of SiliconEdit

Measured by mass, silicon makes up 25.7% of the Earth's crust and is the second most abundant element in the crust, after oxygen. Pure silicon crystals are very rarely found in nature; they can be found as inclusions with gold and in volcanic exhalations. Silicon is usually found in the form of silicon dioxide (also known as quartz), and other more complex silicate minerals.

Silica occurs in minerals consisting of (practically) pure silicon dioxide in different crystalline forms. Amethyst, agate, quartz, rock crystal, chalcedony, flint, jasper, and opal are some of the forms in which silicon dioxide appears. Biogenic silica occurs in the form of diatoms, radiolaria and siliceous sponges.

Silicon also occurs as silicate minerals (various minerals containing silicon, oxygen and one or another metal), for example the feldspar group. These minerals occur in clay, sand and various types of rock such as granite and sandstone. Feldspar, pyroxene, amphibole, and mica are a few of the many common silicate mineral groups.

Silicon is a principal component of many meteorites, and also is a component of obsidian and tektites, which are natural forms of glass.

Occurrence of Iron Edit


The red appearance of this water is due to ferric ion, Iron(III) or Fe3+, in the rocks.

Iron is the sixth most abundant element in the Universe, formed as the final act of nucleosynthesis, by silicon fusing in massive stars. While it makes up about 5% of the Earth's crust, the Earth's core is believed to consist largely of an iron-nickel alloy constituting 35% of the mass of the Earth as a whole. Iron is consequently the most abundant element on Earth, but only the fourth most abundant element in the Earth's crust.[13] Most of the iron in the crust is found combined with oxygen as iron oxide minerals such as hematite and magnetite.

About 1 in 20 meteorites consist of the unique iron-nickel minerals taenite (35–80% iron) and kamacite (90–95% iron). Although rare, iron meteorites are the major form of natural metallic iron on the Earth's surface.

The red color of the surface of Mars is thought to derive from an iron oxide-rich regolith.


  1. Krebs, Robert E. (2006). The History and Use of Our Earth's Chemical Elements: A Reference Guide. Westport, Conn.: Greenwood Press. ISBN 0-313-33438-2. 
  2. Cite error: Invalid <ref> tag; no text was provided for refs named kamienski
  3. Moores, S. (June 2007). "Between a rock and a salt lake". Industrial Minerals 477: 58. 
  4. Handbook of Lithium and Natural Calcium, Donald Garrett, Academic Press, 2004, cited in The Trouble with Lithium 2
  5. Taylor, S.R.; McLennan, S.M.; The continental crust: Its composition and evolution, Blackwell Sci. Publ., Oxford, 330 pp. (1985). Cited in Abundances of the elements (data page)
  6. Cite error: Invalid <ref> tag; no text was provided for refs named
  7. Lithium_Microscope
  8. Clarke, G.M. and Harben, P.W., "Lithium Availability Wall Map". Published June 2009. Referenced at International Lithium Alliance
  9. "Lithium Occurrence". Institute of Ocean Energy, Saga University, Japan. Retrieved on 2009-03-13.
  10. Croswell, Ken (February 1996). Alchemy of the Heavens, Anchor. ISBN 0-385-47214-5, 
  11. Daved M. Meyer, Jason A. Cardelli, and Ulysses J. Sofia (1997). "Abundance of Interstellar Nitrogen". arXiv. Retrieved on 2007-12-24.
  12. Calvin J. Hamilton. "Titan (Saturn VI)". Retrieved on 2007-12-24.
  13. Iron: geological information,, retrieved on 21 May 2008 .