4 ms·

Well it says in the article that De Beers developed a machine to spot synthetic diamonds, so I presume so.

shagie 8y ago
Its likely based on fluorescence. From https://books.google.com/books?id=WQp_rEWV2XUC&printsec=frontcover&hl=en#v=onepage&q=fluorescence&f=false https://books.google.com/books?id=WQp_rEWV2XUC&printsec=fron... > In 1891, B. Walter was the first person to observe the well known cape spectrum in natural diamonds. This series of bands associated with type Ia natural diamonds (that are usually colorless and have blue fluorescence to ultraviolet light), are usually visible in the blue to violet part of the spectrum. ... No synthetic diamonds will show a cape spectrum. It goes on to describe other types of visible tests. The next capture (which I can't fully see on Google Books) describes a device called DiamondSure that fits on a desktop and looks at the cape fluorescence and absorption of particular wavelengths.
- userbinator 8y ago
  That was 18 years ago, the synthetic diamonds today can be made to have the same impurities as natural ones and show up with the same spectrum.
  - ridgeguy 8y ago
    Not really. Synthetic diamonds can be readily detected by at least two instruments sold by De Beers.[1] They look at emissive and absorptive optical features that aren't due to impurities, but due to defects (vacancies, stacking faults, interstitials, etc.). These crystal defects are atomic-scale departures from lattice perfection that are inherent to high growth rates (compared to natural diamonds). You can't see them on visual inspection. These machines are expensive, even when sold at De Beer's cost. You won't see them in the corner jewelry store. But for stones > a carat, it's worthwhile to send a gem to services that use these machines to determine whether the stone is, for example, a natural type IIa (the purest of natural diamonds) or a potential synthetic that "needs further characterization". [1] https://www.iidgr.com https://www.iidgr.com

Its likely based on fluorescence. From https://books.google.com/books?id=WQp_rEWV2XUC&printsec=frontcover&hl=en#v=onepage&q=fluorescence&f=false https://books.google.com/books?id=WQp_rEWV2XUC&printsec=fron... > In 1891, B. Walter was the first person to observe the well known cape spectrum in natural diamonds. This series of bands associated with type Ia natural diamonds (that are usually colorless and have blue fluorescence to ultraviolet light), are usually visible in the blue to violet part of the spectrum. ... No synthetic diamonds will show a cape spectrum. It goes on to describe other types of visible tests. The next capture (which I can't fully see on Google Books) describes a device called DiamondSure that fits on a desktop and looks at the cape fluorescence and absorption of particular wavelengths.

userbinator 8y ago
That was 18 years ago, the synthetic diamonds today can be made to have the same impurities as natural ones and show up with the same spectrum.
- ridgeguy 8y ago
  Not really. Synthetic diamonds can be readily detected by at least two instruments sold by De Beers.[1] They look at emissive and absorptive optical features that aren't due to impurities, but due to defects (vacancies, stacking faults, interstitials, etc.). These crystal defects are atomic-scale departures from lattice perfection that are inherent to high growth rates (compared to natural diamonds). You can't see them on visual inspection. These machines are expensive, even when sold at De Beer's cost. You won't see them in the corner jewelry store. But for stones > a carat, it's worthwhile to send a gem to services that use these machines to determine whether the stone is, for example, a natural type IIa (the purest of natural diamonds) or a potential synthetic that "needs further characterization". [1] https://www.iidgr.com https://www.iidgr.com