Magma
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Magma crystallization
As magma cools, its various elements combine to form minerals. When one mineral forms, the available ingredients, temperature and pressure gradually change to create different minerals.
Magma Cut
(also developed by a New York firm) has 102 facets, namely:
crown ...
Magma: Rock that forms below the surface of the Earth as a result of volcanic activity.
Mineral: An inorganic element of the Earth of consistent atomic structure and chemical composition.
Magma is molten rock which originates deep within the earth. Magma is formed as rock melts at the intense temperatures and pressures present at great depths within the earth.
As magma cools, various minerals form, depending on the temperature and pressure at a particular location and time. As each type of mineral forms it reduces concentration of, or removes, some of the elements required for its formation.
magma
Magma is molten rock (lava) from which igneous rock forms. Magma is be formed from many types of rocks, including basalt, andesite, dacite, gabbro, and rhyolite
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Magma...Molten silica containing volatile substances in solution, present beneath the surface in certain areas of the earth's crust.
Malleable...Can be flattened by pounding, as in metals.
Mammillary... rounded mineral surface ...
found in magmatic and metamorphic veins
Association:
chlorite, hornblende, rutile, apatite, nepheline, feldspars, quartz, calcite ...
Exhibit a very strong double refraction in transparent rhombohedrons caldera A vast depression at the top of a volcanic cone, formed when an eruption substantially empties the reservoir of magma beneath the cone's summit.
The crystals of gem peridot grow in the slowly cooling magma melt before it is erupted onto the surface. The type of volcanic rock that peridot grows in is called basalt. That is why it is known as the volcanic gem.
This blue silicate mineral occurs as crystals or grains in igneous rocks, only as a result of magma contamination by aluminous sediment.
Sometimes amethyst is also formed when red hot magma i.e. molten rock seeps into the crevices and hollows of a parent rock and gets cooled. It is a complex high temperature silica solution with temperature ranging from 600-1200 degree centigrade.
When rocks are buried deep within the Earth, they melt because of the high pressure and temperature; the molten rock (called magma) can then flow upward or even be erupted from a volcano onto the Earth's surface.
Isotopic dating of inclusions in diamonds has revealed that diamonds and the host rocks that contains them are usually not the same age, indicating that most diamonds do not crystallize from kimberlite or lamproite magma.
Deep within the earth's inferno is a stew of molten rock and gases called magma. As magma wells up within the earth, intense pressure forces the liquid rock toward the earth's surface. It is referred to as lava when it breaks through the surface.
Intrusive, or plutonic igneous material is formed when magma fails to breach the surface, cooling slowly over millions of years to create an "intrusion.
These gemstones are distributed in different metallogenetic provinces in northern Vietnam as ruby in the marbles from the Day Nui Con Voi metamorphic belt-Red River Fault Zone, topaz and aquamarine from the pegmatites related to acid magmatism in ...
This crystallized form of magma is also known as 'feld'. Like its versatility fairly large number of separate minerals can be acquired from feldspar. Among these 20 minerals about nine are well recognized.
Millions of years before, liquid magma had shot up from the bowels of the Earth and solidified shortly before it reached the surface.
Granite - A coarse grained igneous rock containing the minerals mica, quartz and feldspar. Granite forms from the solidification of magma deep below the Earth's surface. The magma cools very slowly, allowing big crystals to be formed.
Overview: Epidote usually occurs in high-pressure, low-temperature calcium-bearing metamorphic rocks and as precipitates from magmatic fluids in igneous formations.
Igneous Rock
Rock formed by the solidification of magma from a volcano.
Iridescence
The play of color in a gemstone resulting from inclusions or layers of minerals.
Rocks formed from erupted volcanic lava or solidified magma.
Imitation Gemstone
Material that has the outward appearance of the gem it is intended to imitate, but which has different physical properties.
The members of this most common solid solution series of the olivine group are the primary crystallization products of silica-poor but magnesium and iron-rich magmas. Olivine frequently coexists with plagioclase and pyroxenes in igneous rocks.
Helens or Stromboli off the coast of Sicily, but the magma originates much deeper, which is what enables the diamonds to be extracted and carried up through the earth.
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 - ...
Mineral - A solid inorganic substance with a crystalline structure formed through a geological processes such as a consolidation of molten magma or movement of land masses in subduction zones.
These are rocks that are formed from erupted volcanic lava or solidified magma.
Imitation ...
Cuprite - Old Dominion Mine, Former collections of J. Lewis, Arizona State University, 9.2cm x 6.2cm
Turquoise - Former collection of Frank Knechtel, 4.0cm x 4.8cm
Barite - Magma Mine, 3.0cm x 3.3cm
Vanadinite ...
Igneous
A substance produced under conditions involving intense heat, such as that which is found in volcanoes. Igneous rock is rock formed by solidification from molten magma.
Stugard (1958) disagreed, observing that the age of Monson gneiss is 370 million years and the younger pegmatites could not be of the same origin. Instead, he proposed that the pegmatites formed later from a magma-like fluid, ...
- A crystallization system having three equal horizontal axes intersecting at 120 degrees, plus a vertical axis of a different length. (Calcite, Beryl, Quartz, etc.)
Hydrothermal - Deposited from a hot solution, generally heated by magmatic heat.
 See also: Mineral, Crystal, Rock, Stone, Color
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