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Some ways by which crystals form are precipitating from a solution, freezing, or more rarely deposition directly from a gas. Attributes of the resulting crystal depend largely on factors such as temperature, air pressure, cooling rate, and in the case of liquid crystals, time of fluid evaporation. Crystallization occurs in two major steps.
Telluric iron is largely divided into two groups, depending on the carbon content. Type 1 is a cast-iron typically containing over 2.0% carbon, while type 2 ranges somewhere between wrought iron and a eutectoid steel. Both types tend to handle weathering in the elements very well, but tend to decompose and crumble very quickly in the dry ...
Fractional crystallization, or crystal fractionation, is one of the most important geochemical and physical processes operating within crust and mantle of a rocky planetary body, such as the Earth. It is important in the formation of igneous rocks because it is one of the main processes of magmatic differentiation . [ 1 ]
2. Thus, cummingtonite is the series intermediate. Manganese also substitutes for (Fe,Mg) within cummingtonite amphibole, replacing B site atoms. These minerals are found in high-grade metamorphic banded iron formation and form a compositional series between Mn 2 Mg 5 Si 8 O 22 (OH) 2 (tirodite) and Mn 2 Fe 5 Si 8 O 22 (OH) 2 (dannemorite).
The effect was discovered in 1969, when amorphous germanium (a-Ge) films crystallized at surprisingly low temperatures when in contact with Al, Ag, Cu, or Sn. [1] The effect was also verified in amorphous silicon (a-Si) films, [2] as well as in amorphous carbon [3] and various metal-oxide films. [4]
In mathematics, the outer automorphism group of a group, G, is the quotient, Aut(G) / Inn(G), where Aut(G) is the automorphism group of G and Inn(G) is the subgroup consisting of inner automorphisms. The outer automorphism group is usually denoted Out(G). If Out(G) is trivial and G has a trivial center, then G is said to be complete.
Iron meteorites, also called siderites or ferrous meteorites, are a type of meteorite that consist overwhelmingly of an iron–nickel alloy known as meteoric iron that usually consists of two mineral phases: kamacite and taenite. Most iron meteorites originate from cores of planetesimals, [3] with the exception of the IIE iron meteorite group. [4]
A hydrous aluminium silicate of iron, which is produced in an environment of low-to-moderate-grade metamorphosed iron deposits, as gray or black crystals in oolitic iron ore. Like other chlorites, it is a product of the hydrothermal alteration of pyroxenes , amphiboles and biotite in igneous rock .