Do carbon lab diamonds pass a diamond test to qualify as real? The answer is both yes and no. There are different ways to diamond test. It's important to know which test a synthetic diamond will pass and which it will fail. Carbon lab diamonds can pass a test in terms of their physical and chemical properties, but when these synthetics pass in front of an expert, the difference is very apparent.

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Natural vs. Lab-Grown Diamonds

Natural diamonds are formed over hundreds of millions – or even billions – of years. This natural process and the time it takes for each unique diamond to form contributes greatly to the worth of a natural diamond.

Carbon lab diamonds are formed using many of the same processes that take place in the earth. This allows lab-grown diamonds to be formed in as little as a week. That's for a 1-carat diamond. A 3-carat diamond can form in as little as a month. Any faster and the diamond crystal will crack during formation. Compared to millions of years, that's much faster – but it's also less meaningful, which is why synthetic diamonds trail natural diamonds in terms of value.

The First Diamond Test

If tested for their physical and chemical properties, both natural and lab-grown diamonds will return similar results. The crystal structure will be the same. The chemical composition will be similar (depending on what other chemicals are included for properties like color). In this way, the terms “synthetic diamonds” or “manufactured diamonds” don't actually refer to the diamond itself. Chemically, these carbon lab diamonds are real diamonds. “Synthetic” and “manufactured” refers to their lab-based process of creation.

However, the similarities stop there, and quickly vanish, when you take carbon lab diamonds before a gemologist or jeweler. Every diamond sold is given a clarity grade by the American Gemological Society (AGS) or Gemological Institute of America (GIA). For example, melee parcels are examined by the GIA for assurance of their quality.

The Second Diamond Test

The GIA has identified many synthetic diamonds that have been fraudulently mixed in with natural ones. It's not that difficult to make these identifications. Carbon lab diamonds have a number of markers that show their lesser worth.

Clarity and inclusions are assessed in these exams. It's here that most lab-grown diamonds are readily apparent as synthetic.

Metal inclusions can also give them away. Lab-grown diamonds use a metal solution to assist in their growth. This means that carbon lab diamonds have metallic inclusions. Magnifying as little as 10x reveals them, making them very obvious to even a cursory examination by an expert using a loupe. These inclusions aren't to be found in natural diamonds. Examining with a loupe is only the most basic step in an expert's examination, and it already reveals diamonds that are artificially created.

Natural diamonds may have other inclusions, some of which are valued – these include crystals, clouds, and various other qualities earned over time as they incorporate other elements or experience volcanic eruptions over millions of years. These inclusions often contribute to rare visual properties that make natural diamonds unique and sought after. They cannot be found in lab-grown diamonds, because they are the result of millions of years of growth, not a week's worth.

Revealing Fakes

There are a number of ways to reveal fake diamonds as well.

A “Diamond Tester” may be used. This is another name for a Thermal Conductivity Probe. This meter measures how thermally conductive a gemstone is. Diamonds are very effective heat conductors – this means it will disperse heat that's applied to it quickly.

A tester for electric conductivity also provides a useful metric. Diamonds conduct electricity very well, whereas many fakes do not.

High-profile weighting separates diamonds from other stones. Scales designed to weigh carats can reveal very small differences in weight between stones. When a stone shows too much difference, it's not a real diamond.


What does this all mean for synthetic diamonds? Value is always based on perception and worth. Polls of the public and diamond price points both reveal that synthetic diamonds are simply not as highly sought out or as valued as natural diamonds.

This makes a great deal of sense. Diamonds are still prized as an expression of love. There's a powerful caution among customers when it comes to trusting lab-made diamonds with this emotion.

Ideally, love is everlasting. That's supposed to be symbolized by a stone made in a lab in a week or a month? Natural diamonds can take more than a billion years to form and be uncovered. They have untold experiences being formed deep within the earth we live on. Each natural diamond is the result of a process that began long before humanity existed. It has earned its place as a symbol of love and care.

Nothing synthetic can match the story of a natural diamond. The symbol that shoppers seek to express something timeless must itself be timeless. They simply don't trust a synthetically created diamond that never took that same journey. It hasn't earned its place as a symbol of love. That is the message that customers still see when it comes to the choice between natural stones and synthetic ones.

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