'Best' is a bit of a relative term. Cultured, or lab grown diamonds, are available in multiple colors from multiple labs.
I would note that currently very few *white* lab grown diamonds are available. D.NEA has made whites up to one carat and Apollo Diamonds has offered some up to 1/3 carat.
Of the cultured yellow diamonds, the major sellers are Gemesis, D.NEA (was Adia), Takara, New Age Diamonds and Chatham. Takara's yellow diamonds seem to be the most consistently 'pure yellow', rather than the more common orange-yellow from the other labs.
D.NEA has the largest selection of blue diamonds. Pink diamonds are available at TakaraDiamonds.com and a few other sites like DiamondsCultured.com (made by Chatham).
I'll add some links to the various sites and you can research from there, as best is really partially dependent on what color you like and what type of cut you want.
Diamond Culture, a new supplier as of October 2009 has a large selection of IGI certified yellow, pink and lime diamonds, all cut in Antwerp.
Created-Diamonds.com is an online retailer of cultured diamonds produced by different labs.
If talking about "simulated" and NOT real synthetic / cultured / laboratory-grown diamond (which has the same properties of natural diamonds) I think the best in fire and brilliance is Moissanite, others are considered cheaper fakes.
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If talking about "simulated" and NOT real synthetic / cultured / laboratory-grown diamond (which has the same properties of natural diamonds) I think the best in fire and brilliance is Moissanite, others are considered cheaper fakes.
The best type of synthetic diamond would most likely be Cubic Zircona, a popular fake jewel that is much cheaper than diamond and unlike other fake jewels it will not change color or become tinted by an outside source for very extended periods of time.
A cultured diamond is made in a laboratory and is not a natural stone, even though it is manufactured from carbon. Industrial diamonds have been made in laboratories in America since the 1950s, and gem-stone quality diamonds only recently. What can be inferred from the phrase in your question is a description of a gem-stone quality diamond (which is always less valuable than a natural diamond).
Diamond Aura is the name of a SIMULATED diamond, NOT a synthetic diamond. Natural diamonds and synthetic (cultured) diamonds are identical in being made of pure carbon highly compressed with a hardness of 10. Cultured diamonds cost from 2/3 to 3/4 the price of natural diamonds. SIMULATED diamonds are NOT made of pure carbon. Cubic Zirconium (zirconium dioxide with hardness 8.5) and Mossanite (silicon carbide with hardness 9.25) are simulated diamonds and cost vastly less than natural or cultured diamonds. Diamond Aura stones have a hardness of 8.5, which suggests that they are cubic zirconium.
The Oklahoma Jewelers Association would recommend that the best place to shop for cultured pearls would be at the Pearl Oasis. The Pearl Oasis offers the best cultured pearls available in different sizes.
An enamel or alkyd.
Wipe down your cultured pearl earrings with a warm damp towel. Do not use toothbrushes or other abrasive items on the pearls because they will be scratched.
The company Cultured Stone produces manufactured stone veneer. Some of the products offered are Cultured Stone, Cultured Brick and Architectural Stone.
Viruses can be cultured in tissue or cell media.
Diamond
The answer is strictly a matter of taste and judgment. There is no overall 'best' diamond.
The Best of Jim Diamond was created in 1999.