Are Lab Grown Diamonds Real? Quality and Science Compared

What Lab Grown Diamonds Actually Are

Lab grown diamonds are real diamonds. This is not marketing language: it is the scientific consensus and the position of every major gemological organisation, including the Gemological Institute of America (GIA) and the International Gemological Institute (IGI). A lab grown diamond has the same chemical composition (pure carbon in a cubic crystal structure), the same physical properties, the same optical characteristics, and the same hardness (10 on the Mohs scale) as a natural diamond.

The only difference between a lab grown diamond and a mined diamond is their origin. Natural diamonds were formed 1 to 3 billion years ago under extreme heat and pressure 100 miles beneath the earth's surface. Lab grown diamonds are formed in weeks or months in a controlled laboratory environment that replicates those conditions.

Two processes are used to create lab grown diamonds: High Pressure High Temperature (HPHT), which recreates the conditions under which natural diamonds form, and Chemical Vapour Deposition (CVD), which builds diamond crystal layer by layer from a carbon-rich gas. Both produce genuine diamond.

The 4Cs Comparison

The 4Cs (Cut, Colour, Clarity, and Carat) apply equally to lab grown and natural diamonds. GIA grades both using the same scale.

Cut

Cut quality is determined by the craftsperson who cuts and polishes the diamond, not by how the diamond was formed. Lab grown and natural diamonds can both achieve Excellent or Ideal cut grades. Because lab grown diamonds are slightly less expensive at equivalent sizes, some manufacturers invest more in cut quality to enhance brilliance, making high-quality cuts more accessible.

Colour

The GIA colour scale runs from D (colourless) to Z (light yellow). Lab grown diamonds can be produced across this entire range. Some CVD lab grown diamonds can exhibit a slight greyish or brownish tint that is different from the yellowish tint common in lower-grade natural diamonds; this can sometimes be corrected through post-growth treatment.

Lab grown diamonds are increasingly available in higher colour grades (D-F colourless) at significantly lower prices than comparable natural stones. A 1-carat D colour VS1 lab grown diamond costs roughly 60 to 80 percent less than the same grade natural diamond.

Clarity

Lab grown diamonds can have inclusions, just as natural diamonds do. The types of inclusions differ slightly: natural diamonds often have mineral crystal inclusions, whereas CVD lab grown diamonds may show strain patterns or metallic inclusions from the growth process. Knowledgeable gemologists can sometimes identify these inclusion types, but the clarity grade itself (the visibility of inclusions under 10x magnification) uses the same FL to I3 scale.

Carat

Carat refers to weight, not size. Because lab grown diamonds have the same density as natural diamonds, they are physically identical in size for the same carat weight. A 1-carat lab grown diamond is the same size as a 1-carat natural diamond.

Certification

Lab grown diamonds should be certified by a reputable gemological laboratory, just as natural diamonds should be. The GIA now grades lab grown diamonds on the same 4Cs scale, and IGI (International Gemological Institute) also provides grading reports for lab grown stones.

Certified lab grown diamonds have their laser inscription and country of origin (laboratory) noted on the certificate. This provides full disclosure and allows the buyer to know exactly what they are purchasing.

Always insist on a GIA or IGI certificate when purchasing a lab grown diamond of significant value. Avoid purchasing uncertified diamonds of any kind.

Can Lab Grown Diamonds Be Distinguished From Natural?

A human cannot distinguish a lab grown diamond from a natural diamond with the naked eye. Even trained gemologists cannot reliably tell them apart visually. The physical and optical properties are identical.

Specialised equipment (De Beers DiamondView, mass spectrometers, spectroscopy tools) can distinguish them by detecting trace elements and structural characteristics. These machines are used by gemological laboratories and major jewellers. Retail jewellers with only standard loupe and microscope equipment generally cannot reliably distinguish lab from natural.

The diamond industry has invested heavily in detection technology specifically because undisclosed mixing of lab grown and natural diamonds in jewellery would be fraudulent. The FTC requires sellers to disclose whether a diamond is lab grown or natural. Selling an undisclosed lab grown diamond as a natural diamond is fraud under US and UK law.

Price Difference: Why Lab Grown Costs Much Less

Lab grown diamonds cost 60 to 85 percent less than comparable natural diamonds as of 2025. This gap has widened significantly since 2020 as production capacity has scaled rapidly. A 1-carat G VS2 natural diamond might retail for $5,000 to $7,000. The same grade lab grown diamond retails for $800 to $1,500.

The price difference does not reflect a quality difference. It reflects the economics of supply: natural diamonds are scarce, take billions of years to form, and require expensive mining operations. Lab grown diamonds take weeks to months to produce in controllable quantities. As production scales, prices have dropped and continue to drop. This is the primary reason the resale value question matters so much when considering lab grown diamonds.