Tuesday, 08/10/2010
The Russian diamond producer Alrosa has booked in the first half of 2010 net income of 2.959 billion rubles (more than 75 million euros).
Moscow (RIA Novosti) - As the company announced on Tuesday, has the receipts in the first six months, according to Russian accounting standards to 13.412 billion rubles (about € 339 million) has almost quadrupled. Over the space of the previous year's Alrosa had yet to lose out from 14.675 billion rubles.
Alrosa is specialized in exploration, production and sales of rough diamonds and in the production of
Wednesday, August 11, 2010
Thursday, August 5, 2010
Diamond Material
DIAMOND. A highly transparent and exceedingly hard crystalline
stone of almost pure carbon, 99% of the isotope carbon 12. When pure,
it is colorless, but it often shows tints of white, gray, blue, yellow, or
green. It is the hardest known substance and is 10 on the Mohs hardness
scale. But the Mohs scale is only an approximation, and the
hardness of the diamond ranges from Knoop 5,500 to 7,000 compared
with 2,670 to 2,940 for boron carbide, which has a Mohs hardness of 9.
The diamond always occurs in crystals in the cubic system and has
a specific gravity of 3.521 and a refractive index of 2.417. Carbon is
normally quadrivalent in flat planes, but in the diamond the carbon
atoms are arranged in face-centered lattices forming interlocking
tetrahedrons and also hexagonal rings in each cleavage plane.
The diamond has been valued since ancient times as a gemstone,
but it is used extensively as an abrasive, for cutting tools, and for
dies for drawing wire. These industrial diamonds are diamonds
that are too hard or too radial-grained for good jewel cutting. Jewel
diamonds have the formation in regular layers, while industrial
diamonds are grown in all directions. Technically these are called
feinig and naetig. Ballas diamonds, valued for industrial drilling,
are formed with the crystallization starting from one central point.
The stones thus formed do not crack in the tool as easily as those with
layer formation. Stones for diamond dies are examined in polarized
light to determine the presence of internal stresses. They are then
drilled normal to the rhombic dodecahedron plane with cleavage
planes parallel to the die-hole axis to obtain the greatest die-service
life. The stones for industrial purposes are also the fragments and the
so-called bort which consists of the cull stones from the gem industry
including stones of radiating crystallization that will not polish well.
Bort also includes a cryptocrystalline variety of diamond in brown,
gray, or black, known as black diamonds, carbonados, or carbons,
found in Brazil in association with gem diamonds. The carbons have
no cleavage planes, are compact, and thus offer greater resistance to
breaking forces. The carbons vary greatly in quality and hardness.
Some rare natural diamonds of South America contain small amounts
of aluminum and other elements which give stability to the crystal
above the normal disintegrating temperature. These diamonds are
not suitable as gemstones but are efficient semiconductors.
From the diamond materials handbook please purchase, if you'd like to read more
stone of almost pure carbon, 99% of the isotope carbon 12. When pure,
it is colorless, but it often shows tints of white, gray, blue, yellow, or
green. It is the hardest known substance and is 10 on the Mohs hardness
scale. But the Mohs scale is only an approximation, and the
hardness of the diamond ranges from Knoop 5,500 to 7,000 compared
with 2,670 to 2,940 for boron carbide, which has a Mohs hardness of 9.
The diamond always occurs in crystals in the cubic system and has
a specific gravity of 3.521 and a refractive index of 2.417. Carbon is
normally quadrivalent in flat planes, but in the diamond the carbon
atoms are arranged in face-centered lattices forming interlocking
tetrahedrons and also hexagonal rings in each cleavage plane.
The diamond has been valued since ancient times as a gemstone,
but it is used extensively as an abrasive, for cutting tools, and for
dies for drawing wire. These industrial diamonds are diamonds
that are too hard or too radial-grained for good jewel cutting. Jewel
diamonds have the formation in regular layers, while industrial
diamonds are grown in all directions. Technically these are called
feinig and naetig. Ballas diamonds, valued for industrial drilling,
are formed with the crystallization starting from one central point.
The stones thus formed do not crack in the tool as easily as those with
layer formation. Stones for diamond dies are examined in polarized
light to determine the presence of internal stresses. They are then
drilled normal to the rhombic dodecahedron plane with cleavage
planes parallel to the die-hole axis to obtain the greatest die-service
life. The stones for industrial purposes are also the fragments and the
so-called bort which consists of the cull stones from the gem industry
including stones of radiating crystallization that will not polish well.
Bort also includes a cryptocrystalline variety of diamond in brown,
gray, or black, known as black diamonds, carbonados, or carbons,
found in Brazil in association with gem diamonds. The carbons have
no cleavage planes, are compact, and thus offer greater resistance to
breaking forces. The carbons vary greatly in quality and hardness.
Some rare natural diamonds of South America contain small amounts
of aluminum and other elements which give stability to the crystal
above the normal disintegrating temperature. These diamonds are
not suitable as gemstones but are efficient semiconductors.
From the diamond materials handbook please purchase, if you'd like to read more
Wednesday, June 23, 2010
platinum diamond earrings
These classic diamond stud earrings are a timeless gift. They feature round-cut diamonds with a total carat weight of 1 carat. The diamonds are mounted in a four-prong setting on platinum posts for pierced ears. The posts are threaded, and the rounded backings screw on for a comfortable and secure fit. These are exceptional quality diamonds. With a minimum G-H color rating, they are in the upper-most range of near-colorless and appear dazzling white to the eye. They have a minimum clarity of VS2, meaning there are very small
Wednesday, September 17, 2008
Tuesday, September 16, 2008
rough diamonds wanted
Rough diamonds are wanted by international buyers. If you have uncut, rough diamonds for sale, pleas contact rough diamonds wanted.
Wednesday, August 6, 2008
diamond brokers
This blog will be about offers and requests of diamonds. If you interested into the diamond trade, please visit diamond brokers.
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