Technology has been one of the biggest boons to the diamond and gemstone industry, but more modernization has also led to an increase in the spread of misinformation. Although natural, earth-formed diamonds and lab-grown diamonds are structurally and chemically identical, many consumers are wary of lab-grown diamonds. This has led to a demand for jewelers to become acquainted with identifying their stock.

Thankfully, there exists diamond-screening equipment for jewelers to do just that, yet the very first step before jewelers can use screening equipment is knowledge of their product and clean gems. Excessive dirt can cause a machine to give a false reading on a natural diamond.

Some machines that use “glow in the dark” phosphorescence ultraviolet (UV) light to check for HPHT (high pressure-high temperature) lab-grown diamonds cannot read simulants like moissanite and cubic zirconia, so it is of vital importance that jewelers prevent simulant “contamination.” Using these machines, lab-grown HPHT diamonds glow brightly due to the flux they are grown in (although some natural diamonds can do this, it is rare).

For machines that test using short-wave transparency to screen for lab-grown Type II diamonds created through chemical vapor deposition (CVD) or HPHT, the machine examines opacity, although it is important to know only colorless diamonds can be read. Type II diamonds show right through while Type I diamonds are opaque—with one exception: Type IaB diamonds can be deceptive and show transparently.

When dealing with these, a jeweler should use UV light testing to determine stone type. Synthetic Type IaB diamonds have an incredibly strong, very blue fluorescence while natural diamonds exhibit a medium- to strong-blue fluorescence under long-wave UV.

Diamonds that exhibit stronger fluorescence under long-wave UV and weak short-wave UV fluorescence are more likely to be natural, though additional testing is always suggested to verify results. Many lab-grown diamonds glow stronger under short-wave UV than long-wave UV, though, once again, it is important to note that this will only work on colorless diamonds. In instances where fluorescence under both types of UV waves is similar, further testing is necessary.

So, how can jewelers protect themselves from false readings? The best way is to buy from reputable, secure vendors. If a jeweler does the testing themselves and has their machine refer the diamond, the diamond can be sent off to a testing company. Doing so is inexpensive and gives jewelers access to more advanced equipment without having to purchase it.

Ultimately, and, perhaps, mostly importantly, jewelers should always be aware of two things: just because a diamond is referred by a machine doesn’t immediately mean it’s lab-grown and cause for concern—it simply requires further testing (because false readings do happen)—and there is no detection equipment, only screening equipment.

Being well-informed leads to more educated, happier consumers, and that is the key to fighting misinformation and, hopefully, will lead to less panic around lab-grown stones.

See what Stuller does to ensure the integrity of our diamonds in the video below.