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The eluviation of chelate compounds is the downward movement of soil chelates. The eluviation of chelate compounds can be affected by: Acidity. Organic acids produced under acidic conditions can increase the solubility of metal elements such as iron and aluminum, thereby enhancing soil eluviation. Iron and aluminum are easily leached at low pH.
The filtration of iron compounds from a very sensitive clay from Labrador, Canada, resulted in a 30 t/m reduction in apparent preconsolidation pressure. [1] Coop and Airey (2003) show that for carbonate soils, cementation develops immediately after deposition and allows the soil to maintain a loose structure.
Prior to 2004, the principal use of palladium in jewelry was the manufacture of white gold. Palladium is one of the three most popular alloying metals in white gold (nickel and silver can also be used). [41] Palladium-gold is more expensive than nickel-gold, but seldom causes allergic reactions (though certain cross-allergies with nickel may ...
Platinum can occur as a native metal, but it can also occur in various different minerals and alloys. [16] [17] That said, Sperrylite (platinum arsenide, PtAs 2) ore is by far the most significant source of this metal. [18] A naturally occurring platinum-iridium alloy, platiniridium, is found in the mineral cooperite (platinum sulfide, PtS).
[citation needed] Over geological time scales, very few metals can resist natural weathering processes like oxidation, so mainly the less reactive metals such as gold and platinum are found as native metals. The others usually occur as isolated pockets where a natural chemical process reduces a common compound or ore of the metal, leaving the ...
Soil formation, also known as pedogenesis, is the process of soil genesis as regulated by the effects of place, environment, and history. Biogeochemical processes act to both create and destroy order within soils.
These metal-bearing complexes facilitate transport of metals within aqueous solutions, generally as hydroxides, but also by processes similar to chelation. This process is especially well understood in gold metallogeny where various thiosulfate, chloride, and other gold-carrying chemical complexes (notably tellurium -chloride/sulfate or ...
The Goldschmidt classification, [1] [2] developed by Victor Goldschmidt (1888–1947), is a geochemical classification which groups the chemical elements within the Earth according to their preferred host phases into lithophile (rock-loving), siderophile (iron-loving), chalcophile (sulfide ore-loving or chalcogen-loving), and atmophile (gas-loving) or volatile (the element, or a compound in ...