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  2. Heavy metals - Wikipedia

    en.wikipedia.org/wiki/Heavy_metal_(elements)

    The Earth's crust is made of approximately 5% of heavy metals by weight, with iron comprising 95% of this quantity. Light metals (~20%) and nonmetals (~75%) make up the other 95% of the crust. [ 89 ] Despite their overall scarcity, heavy metals can become concentrated in economically extractable quantities as a result of mountain building ...

  3. Allende meteorite - Wikipedia

    en.wikipedia.org/wiki/Allende_meteorite

    The Allende meteorite is the largest carbonaceous chondrite ever found on Earth. The fireball was witnessed at 01:05 on February 8, 1969, falling over the Mexican state of Chihuahua . [ 1 ] After it broke up in the atmosphere , an extensive search for pieces was conducted and over 2 tonnes (2.2 tons) were recovered.

  4. Discovery of chemical elements - Wikipedia

    en.wikipedia.org/wiki/Discovery_of_chemical_elements

    De Boisbaudran found a new earth in erbia. [147] 18 Argon: 1894 Lord Rayleigh and W. Ramsay: 1894 Lord Rayleigh and W. Ramsay They discovered the gas by comparing the molecular weights of nitrogen prepared by liquefaction from air and nitrogen prepared by chemical means. It is the first noble gas to be isolated.

  5. Hoba meteorite - Wikipedia

    en.wikipedia.org/wiki/Hoba_meteorite

    The Hoba meteorite is thought to have impacted Earth less than 80,000 years ago. It is inferred [4] that the Earth's atmosphere slowed the object in such a way that it impacted the surface at terminal velocity, thereby remaining intact and causing little excavation (expulsion of earth). Assuming a drag coefficient of about 1.3, the meteor ...

  6. Meteorite - Wikipedia

    en.wikipedia.org/wiki/Meteorite

    The 60-tonne, 2.7 m-long (8.9 ft) Hoba meteorite in Namibia is the largest known intact meteorite.[1]A meteorite is a rock that originated in outer space and has fallen to the surface of a planet or moon.

  7. Big Bertha (lunar sample) - Wikipedia

    en.wikipedia.org/wiki/Big_Bertha_(lunar_sample)

    It was found in the Fra Mauro region of the Moon. Big Bertha is the first discovered meteorite from Earth, and the embedded meteorite portion is the oldest known Earth rock. At 8.998 kg (19.84 lb), this breccia rock is the third largest Moon sample returned during the Apollo program, behind Big Muley and Great Scott.

  8. Iridium - Wikipedia

    en.wikipedia.org/wiki/Iridium

    The Willamette Meteorite, the sixth-largest meteorite found in the world, has 4.7 ppm iridium. [59] Iridium is one of the nine least abundant stable elements in Earth's crust, having an average mass fraction of 0.001 ppm in crustal rock; gold is 4 times more abundant, platinum is 10 times more abundant, silver and mercury are 80 times more ...

  9. Xenon isotope geochemistry - Wikipedia

    en.wikipedia.org/wiki/Xenon_isotope_geochemistry

    [11] [12] If the BSE represents Earth's chemical composition, [2] the total 127 I in the BSE ranges from 2.26×10 17 to 3.23×10 17 moles. The meteorite Bjurböle is 4.56 billion years old [ 13 ] with an initial 129 I/ 127 I ratio of 1.1×10 −4 , [ 14 ] so an equation can be derived as