Ore-forming elements

Within the limits of the positive anomalies of the ore-forming elements the siderophile... 

A model of an ore geochemical system has been developed (Goldberg et al, 2003), which can be applied to ore entities of various categories ore bodies, deposits and ore regions. The nuclear section of the system contains a zone of accumulation of the principal ore and associated elements. The peripheral areas contain zones of depletion of ore-forming elements. Anomalies of siderophile elements (Ni, Co, Mn, Ti, V, Cr), which are the subject of this paper, are located on the periphery of the nuclear sections of these systems. 

In areas of accumulation of ore-forming elements the siderophile elements, as a rule, form zones of lower concentrations relative to the background concentration. Experience shows that these zones most probably contain ore bodies and deposits... 

The analysis of rock samples was conducted in the chemical laboratory in Ust-Kamenogorsk, Kazakhstan. by inductively coupled plasma mass spectrometry, and the equipment used was an ELAN-6100 (US) mass spectrometer. In the present abstract the distribution of two elements zinc (as the basic ore-forming element) and titanium (of the siderophile element) is examined. The sensitivity of the analysis is 5 ppm for Zn and 0.05% for Ti. The analytical results for Zn and Ti are presented on contoured... 

Zyryanovsk. The main VMS deposits are localised in zones of enrichment of the ore-forming elements. The depletion zones of the ore-forming elements... 

Besides fission products, the various forms of known but newly formed elements in the spent nuclear fuel, there is a small but significant amount of fissionable, or fissile, material in the SNF. This is quite important. There is some unused, unfissioned U-235 that has become too dilute to use. Like natural uranium ores in which chain reactions do not... 

Iron is one of the most abundant metals in the upper crust of the earth. It is the fourth mineral-forming element (after silicon, oxygen, and aluminum), constituting about 5% of the earth s crust (see Table 1). Large deposits of its ores are numerous, widely distributed, and easily accessible. 

Nickel is a silver-white, lustrous, hard, malleable, ductile, ferromagnetic metal that is relatively resistant to corrosion and is a fair conductor of heat and electricity. Nickel is a ubiquitous trace metal that occurs in soil, water, air, and in the biosphere. The average content in the earth s crust is about 0.008%. Nickel ore deposits are accumulations of nickel sulfide minerals (mostly pentlandite) and laterites. Nickel exists in five major forms elemental nickel and its alloys inorganic, water-soluble compounds (e.g., nickel chloride, nickel sulfate, and nickel nitrate) inorganic, water-insoluble compounds (e.g., nickel carbonate, nickel sulfide, and nickel oxide) organic, water-insoluble compounds and nickel carbonyl Ni(CO). ... 

Elements slightly heavier than uranium, produced by radioactive decay (see later), are found in tiny amounts in natural uranium ores. Plutonium (element 94) has also been found in nature, a product of the element-forming processes that happen in dying stars. So it is a tricky matter to put a precise number on the natural elements. 

Joseph Lockyer (1836-1920) was one of the pioneers of solar spectroscopy. In examining the spectra of solar prominences in 1869, Lockyer noticed an absorption line that he could not identify. Reasoning that it represented an element not present on Earth, he proposed a new element - helium, from the Greek word helios for Sun. This idea failed to achieve acceptance from Lockyer s scientific colleagues until a gas having the same mysterious spectral line was found 25 years later in rocks. The helium in terrestrial uranium ore formed as a decay product of radioactive uranium. Thus, this abundant element was first discovered in the Sun, rather than in the laboratory. Lockyer s cosmochemical discovery was recognized by the British government, which created a solar physics laboratory for him. Lockyer also founded the scientific journal Nature, which he edited for 50 years. 

Common rock-forming element. Enriched in many rocks, ores, soils, mine wastes, smelter emissions, etc. Pyrite (an iron sulfide) is a source of readily available iron and occurs in many different rocks and ores. 

The elements that make up Group 16 (VIA) of the periodic table are sometimes called the chalcogens. This name comes from the Greek word for ore forming, chalkos. The first two elements in the family, oxygen and sulfur, are often found in ores. Tellurium is the next to last member of that family. The periodic table is a chart that shows how chemical elements are related to one another. 

Fig. 12-4. Stratigraphic zonation of ore-forming and ore-associated elements in DDH 42, Howard s Pass (XY) deposit (from Goodfellow et al., 1983).

In summary, there is no evidence that the higher volatility of Hg relative to the target elements, Pb and Zn, has resulted in its wider dispersion during the ore-forming processes of the sediment-hosted massive sulphide deposits described here. 

Stable isotopes of the elements oxygen, hydrogen, sulphur, nitrogen and carbon can provide useful insights into weathering mechanisms, ecosystem dynamics, hydrothermal ore-forming systems, climate change and... 

Gangue elements, like Ca, Mg, Si, etc. which remain in the oxidic state, as well as the AI2O3 formed are contained in the slag. Carbide-forming elements, like Ti, Mb, Ta, and Mo, appear in the crystal mass and should be contained in the ore concentrates only in low concentration. Elements which are reduced but do not form carbides are dissolved in the iron. 

More commonly, selenium enters the air from burning coal or oil. Much of the selenium in air is attached to fly ash and to suspended particles. The elemental selenium that may be present in fossil fuels forms selenium dioxide when burned. Selenium dioxide can then form selenious acid with water or sweat. Selenium anhydride is released during the heating of copper, lead, and zinc ores when there is selenium in them. Hydrogen selenide breaks up rapidly in air to form elemental selenium and water, thus eliminating the danger from this compound for most people, except those who are exposed to it in their workplace. 

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