Terrestrial minerals

Phosphorus is the eleventh element in order of abundance in crustal rocks of the earth and it occurs there to the extent of 1120 ppm (cf. H 1520 ppm, Mn 1060 ppm). All its known terrestrial minerals are orthophosphates though the reduced phosphide mineral schrieber-site (Fe,Ni)3P occurs in most iron meteorites. Some 200 crystalline phosphate minerals have been described, but by far the major amount of P occurs in a single mineral family, the apatites, and these are the only ones of industrial importance, the others being rare curiosities. Apatites (p. 523) have the idealized general formula 3Ca3(P04)2.CaX2, that is Caio(P04)6X2, and common members are fluorapatite Ca5(P04)3p, chloroapatite Ca5(P04)3Cl, and hydroxyapatite Ca5(P04)3(0H). In addition, there are vast deposits of amorphous phosphate rock, phosphorite, which approximates in composition to fluoroapatite. " These deposits are widely... 

Erd-. earth, earthy, terrestrial, mineral, ground, soil. geo-, -ableitung, /, (Elec.) earth connection, ground, -achse, /. axis of the earth, erdacht, p.a. devised, invented. 

The isotopic studies of terrestrial minerals and Allende inclusions have clearly established the capabilities of the Chicago ion probe to perform precise isotopic measurements on femtogram... 

Phosphorus is the eleventh most abundant element in the crystal rocks of the earth. Elemental phosphorus does not exist in nature and all of its known terrestrial minerals are orthophosphates found in phosphate rocks which occur in vast deposits throughout the world. Phosphate rock is the starting material for the industrial manufacture of elemental phosphorus. White phosphorus is produced by heating phosphate rock with sand and coke in an electric furnace according to Equations 5.19 ... 

Liese, H. C., Selected terrestrial minerals and their infrared absorption spectral data 4000 — 300 cm1, in Infrared and Raman spectroscopy of lunar and terrestrial materials (ed. Karr, C.) p. 197, New York, S. Francisco, London, Academic Press 1975... 

Karr, C. Jr. Infrared and Raman Spectroscopy of Lunar and Terrestrial Minerals Academic Press New York, 1975 375 pp. 

The Ti(TV) oxidation state is more stable in terrestrial minerals than the Ti(III) state so that the existence of Fe2+-Fe3+-Ti4+ assemblages are much more common than are Ti3+-Ti4+ assemblages. Thus, although Ti3+— Ti4 IVCT transitions have been suggested to occur in several titaniferous silicates, including melanite garnets (Moore and White, 1971), andalusite (Faye and Harris, 1969), synthetic... 

Although Cr2+ ions are rare and unstable in terrestrial minerals, their presence is suspected in olivines and pyroxenes from the Earth s Mantle and the Moon (Bums, 1975a Smith, 1971). Crystal field spectra exist for these silicates, as well as other synthetic Cr2+-bearing phases, and parameters are summarized in table 5.12. Just one spin-allowed transition, corresponding to 5Eg - 5T2g, might... 

Adams, J. B. (1975) Interpretations of visible and near-infrared diffuse reflectance spectra of pyroxenes and other rock-forming minerals. In Infrared and Raman Spectroscopy of Lunar and Terrestrial Minerals. (C. Karr Jr., ed. Academic Press, New York), pp. 91-116. 

Spectroscopy of Lunar and Terrestrial Minerals. (C. Karr Jr, ed. Academic Press, New York), pp. 91-116. 

Huntress, W., Jr., and L. Wilson (1972). An ESCA study of lunar and terrestrial minerals. Earth Plan. Sci. Lett. 15, 59-64. 

In the beginning of the nineteenth century, analytics of plant matter samples started with that of plant ashes. In addition, no methods were available then which could have enabled intact biological materials to be digested for complete, no-Ioss analyses without burning them before. Hence, volatile elements then could not be detected, let alone quantified in biomass. Elements then found in plant ashes (Fe, Na, K, Ca, etc.) were both abundant and had been discovered in other sources before. As, e.g., no spectroscopic methods whatsoever were at hand earlier than about 1860, technical prospects for trace analysis then were dim at best (there are very few instances of elements detected in environmental samples/spectra prior to their isolation on Earth helium (in 1868) and techne-tinm (in 1952) were found in stellar spectra before being isolated from or detected in terrestrial minerals... 

The inter-aeon boundary between the Hadean and Archean is presently not defined (Nisbet, 1991). There are various options (i) the date of the first life on Earth (ii) the date of the last common ancestor (iii) a round number, such as exactly 4 Ga—4,000,000,000 years ago (iv) the oldest record of a terrestrial rock ( 4 Ga ago) (v) the oldest record of a terrestrial mineral crystal (—4.3-4.4 Ga ago). 

The straightforward explanation was that element 61 was not just rare but rarest element. Its abundance was assumed to be much lower than that of other rare-earth elements and the available analytical techniques were not sensitive enough to identify its traces in the terrestrial minerals. New more sensitive methods were needed for the purpose. 

Chemists failed in looking for element 61 in the terrestrial minerals. It was theoretical physics whose fate it was to open up the envelope where nature had sealed element 61. But when the envelope was open the scientists (not for the first time ) were disappointed. The envelope was empty. 

Swinne made a theoretical study of the variation of various properties of radioelements and, in particular, half-lives. He came to the conclusion that the elements directly following uranium had to have short half-lives. But the elements with the numbers in the ranges between 98 and 102 and between 108 and 110 could be expected to have sufficiently long half-lives. Where to look for them Swinne suggested that the best bet would be not terrestrial minerals but space objects. This is why he studied the dust of space origin collected in Greenland. All this was quite fascinating but not substantiated and therefore looked like doomed for oblivion. 

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