Wednesday, October 27, 2010

Lab created diamonds facts

Lab created diamonds are officially called synthetic diamonds. Though these diamonds are sometimes characterized as being fake they have identical molecular structure like the real diamonds, and the only difference between them and their natural brothers is the place of their origin (Earth's mantle or lab).

Lab created diamonds can even have superior quality compared to natural diamonds, for instance greater purity or hardness.

In 1893 Ferdinand Frédéric Henri Moissan synthesized first artificial diamonds by heating charcoal to a temperature of 4000°C with iron in a carbon crucible in an electric furnace, after which in electric furnace electric arc was struck between carbon sticks inside blocks of lime. This partially successful experiment opened the door for many others and the final breakthrough came in 1954 when General Electric team made first commercially successful synthesis of diamond by using an elegant "belt" press apparatus which significantly raised the pressure from 6 to 18 GP-a and the temperature to 5000°C, using a pyrophyllite container, and having the graphite dissolved within molten nickel, cobalt or iron, a "solvent-catalyst". However synthetic gem-quality diamond crystals were not produced until the year 1970, and again by General Electric, although these first examples were predominantly cubic and octahedral in form, and due to contamination with nitrogen, always yellow to brown in color and the next step was creation of artificial white diamonds without inclusions.

Many of artificial stones were developed since then, including real giants of up to 11,000 carats, although vast majority of lab created diamonds is small with weight of 1 to 1,5 carats. Two main methods for producing synthetic diamonds are HPHT (High Pressure, High Temperature) method and Chemical Vapor Deposition (CVD) method.

HPHT method simulates natural conditions deep in the Earth’s core from where nature diamonds originate and to achieve this they use large presses that can weigh a couple of hundred tons to produce a pressure of 5 GPa at 1,500 degrees Celsius in order to reproduce needed conditions.

CVD method creates conditions that are necessary for carbon atoms in a gas to settle on a substrate in crystalline form. This method doesn't need high pressure, in fact this method uses low pressure, only 1 to 27 kPa and is based on supplying gases into chamber and then energizing them, after which conditions for diamond growth on the substrate are created.

Lately some celebrities opted to wear lab created diamonds because these diamonds are definitely conflict free.

Lab created diamonds cost significantly less than the diamonds created in nature, and as said before they can have superior quality compared to natural diamonds.

Diamond simulants are not the same as lab created diamonds because diamond simulants such as cubic zirconia or rhinestones are not real diamonds, they only look like diamonds, but have completely different properties than the real diamonds, unlike lab created diamonds which have the same properties as natural diamonds.

In order to tell whether the diamond was created in nature or in the lab there are some different methods available (like for instance Spectroscopy). This means that there is really no way amateur could see the difference between diamonds created in nature from the ones created in lab so if you decide to go for lab created diamond for your diamond jewelry nobody will see the difference.


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