Cultured gemstones, also known as synthetic or lab-grown, are gems created in a laboratory setting using advanced technological processes. They are chemically identical to their naturally occurring mined counterparts.
We regularly work with a few lab-grown gemstones: sapphire, ruby, emerald, spinel, moissanite, and diamonds.
One difference between cultured gemstones and natural gemstones is their origin. Natural gemstones are formed over millions of years in the Earth's mantle and brought to the surface through volcanic activity or mining. Cultured gemstones, on the other hand, are created in a matter of weeks using various techniques such as flux growth, hydrothermal synthesis, and CVD.
Visually there is a big difference between some lab-grown colored gemstones and their natural counterpart. Typically sapphires, emeralds, and rubies will have inclusions in them, which affect the stone's clarity and sometimes lower its durability – and high-clarity natural versions can be costly. Whereas the lab-grown versions are basically flawless at a much lower price. In the case of emeralds, this higher clarity also makes them more durable than their natural counterpart.
Another visual difference is the consistency of color. Natural sapphires often have color banding or color zones. In contrast, the color will be more consistent though the entire stone with a lab-grown version. It is also easier to get a similar color stone with the lab-grown versions, whereas the natural ones are one-of-a-kind.