Crystallization can be divided into two stages. Primary nucleation is the nucleation of a new crystal on some seed or impurity or surface irregularity.
Summary: Recrystallization is the technique of purifying solids based on their different solubility.
crystallization
Crystallization is the process in which magma solidifies into solid, crystalline rock.
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Gas crystallization
While some gems grow on a solid base, others form inside gas bubbles. Gas bubbles are formed during a volcanic eruption when rising magma undergoes a rapid reduction in pressure.
Melt/Crystallization Formation
As magma cools, various minerals form, depending on the temperature and pressure at a particular location and time.
crystallization (v) the process of forming a crystal structure.
cardinal [gemstones] (n) an historical/obsolete classification of five gemstones (diamond, emerald, ruby, sapphire and amethyst) considered to be of highest importance or value.
Formed by crystallization, similar to crystal in texture.
Cubic Zirconia ...
recrystallization The diagenetic process by which unstable minerals in buried sediment are transformed into stable ones. reflection The event occurring when light hits a material and bounces off of it.
These changes include recrystallization, lithification and precipitation. Sedimentary diagenesis takes place at depths of less than a few kilometers within the earth's crust and occurs at temperatures of less than 200° Celsius.
It is, however, characterized by the rhombohedron crystallization. Calcite is colorless or white and can become green, pink, peach, golden, orange, yellow, red, blue, gray, or black when other compounds blend with it during formation.
Tetragonal System - Crystallization system having two equal horizontal axes at right angles to each other, and a vertical axis of a different length at right angles to the other two. (Zircon, Cassiterite) ...
Garnet: A family of stones having many varieties differing in color and in their constituents, but all are silicates with the same isometric crystallization and conforming to the same general chemical formula.
The method incorporates crystallization of a gem material from a solution in a flux rather than from molten ingredients such as the flame fusion or Czochralski method.
During the process of crystallization in the proper environment, crystals assume various geometric shapes dependent on the ordering of their atomic structure and the physical and chemical conditions under which they grow.
The boundaries of inhomogenities which result from changing conditions during the crystallization process of the diamond are called growth lines or grain lines.
Granular, botryoidal, stalactite, massive, and fan-shaped forms can develop from such crystallization. The directional orientation of the tetrahedra causes its strong piezoelectric and pryoelectric characteristics.
quartzite - A metamorphic rock produced by the recrystallization of a sandstone under heat and pressure, consisting of a granular, interlocking mass of disoriented quartz crystals with irregular boundaries.
Requires a source of fluorine; during the late-stage crystallization of certain types of igneous rocks fluorine vapor is present and can be trapped in pegmatites or gas cavities in volcanic rocks.
Some chemical feature of A not found in B might have caused crystallization of certain minerals in the former, which did not appear in the latter.
Thus both melting and dissolving went on together and as a result many fine gem minerals of magnificent crystallization were formed during the subsequent cooling.
It cools to a rigid state, however, without crystallization. A variety of constituents may be used to create it.
Because Canada Hill granite are among the oldest granites in the region, much of the Grenville and Pre-Cambrian faulting has been obscured through rehealing, injection, or recrystallization,.
They are created by an irregular crystallization when the diamond is formed and can be colorless, white or colored. Colorless grain lines are traditionally not noticed unless there are a mass of them in one area of the diamond.
Monoclinic: A system of crystallization wherein two crystal axes intersect obliquely and are perpendicular to the third. See Amphibole.
Crystal inclusions formed due to improper crystallization of diamond.
Heart shape cut
A fancy cut in diamonds, where the cut resembles the shape of a heart.
It is formed from volcanic lava that cooled too quickly for significant crystallization to occur. Nodular obsidian fragments that are transparent are termed Apache Tears. They can be naturally rounded due to water erosion and abrasion.
Inclusions - Internal flaws in a gemstone such as specks, carbon, tiny bubbles, hairlines and other imperfections of crystallization.
Natural igneous rock formation usually characterized by a coarse texture caused by crystallization from an exceptionally fluid magma rich in mineralizers containing rare elements
Rarity factors - ...
Surface Graining (SGr)
Visible surface lines caused by irregular crystallization during formation.
Surface Graining Inclusion Photos
Human Caused Surface Blemishes ...
Gemstones naturally occur with characteristic marks, called inclusions, that were created either during the process of crystallization of the gemstone or during the polishing process.
Chatham Ruby: this ruby is very hard to distinguish from natural ruby. It is created from a melt - recrystallization process. It has the same corundum (Al2O3) chemical structure, and shares the same general types of flaws. Sample 1.
It is found native in the earth, and is also produced by the evaporation and crystallization of sea water and other water impregnated with saline particles. Salt is used extensively in ground or granulated form as a food seasoning and preservative.
Mother Nature is not perfect though and as Diamonds grew in the Earth millions of years ago, Nitrogen found it's way into the crystallization process. Nitrogen is the common element that gives most Diamonds their Colors (like Yellow, Brown and Gray).
Natural blue diamonds are among the rarest of colored diamonds and their color comes from the presence of minute amounts of the element boron incorporated within the crystal lattice of the stone during its crystallization process.
They are coarse because the liquid residue at the time of their crystallization contained a high percentage of water and other volatile elements that did not go into the makeup of the common minerals of granite, and were concentrated in the residue.
Zircon is a remarkable mineral, if only for its almost ubiquitous presence in the crust of Earth. It is found in igneous rocks (as primary crystallization products), in metamorphic rocks and in sedimentary rocks (as detrital grains).
specks of iron; a substance formed when the crystal was being formed, e.g. a gas bubble or a change after the crystal was formed, e.g. by heating which causes chamical alteration and recrystallization.
Great care must be taken in heat treating tourmaline both to avoid temperature shock and to make sure the treatments do not exceed 700° centigrade. At a temperature of about 725°C tourmaline loses essential water of crystallization, ...
 See also: Crystal, Crystals, Stone, Gemstone, Mineral
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