There are three kinds of diamond stone that you can encounter as a consumer:
Natural diamonds: These are diamonds sourced from mines. These stones are entirely made up of carbon atoms which are structured in diamond lattice and typically formed 140 to 190 kilometres in the Earth’s mantle. A real diamond forms over a period of a billion years or more. Diamonds are the hardest known naturally occurring substance and cannot be cut or scratched by any other known substance other than another diamond. This quality together with a diamonds reflective quality have long made diamond an extremely coveted stone for jewellery.
Lab made diamonds: Lab made diamonds (sometimes called synthetic diamonds) are still technically real diamonds in the sense that they share all the same atomic qualities and physical characteristics of a mined diamond. These include the same chemical composition, crystalline structure and physical qualities including reflectivity, hardness and density. Such diamonds are produced by utilizing two processes: High Pressure-High Temperature (HPHT) and Chemical Vapor Depositio n (CVD). In both processes, a small diamond seed is placed in an environment that contains carbon. Under suitably controlled conditions, the diamond grows, atom-by-atom, layer-by-layer, recreating nature’s process. Manufactures of such stones include Gemesis, Adamas and Centaurus Diamond Technologies.
Simulants: Cubic Zirconia, rhinestone, moissanite, white sapphire and lead crystal are often used as alternatives to diamonds in jewellery. All these stones are known as simulants with cubic zirconia being the most widely used over the last two decades. Although to the naked eye these stones may appear to have the same physical qualities as a diamond, their structure, composition and even hardness, reflectivity and density differ substantially from diamonds. These are much less costly to produce and as such are used as a lower cost alternative to diamonds.
How do you know whether a stone is synthetic, from a mine or simulant?
A certified gemologist will be able to quickly differentiate whether a stone is a simulant or not. However due to the identical make up of lab-made diamonds and mined diamonds it is not possible for even a gemologist to differentiate the two. Certification from the lab made diamond manufacturer can only confirm the source. Furthermore, lab made diamonds are typically not larger than 2.5carats whereas naturally occuring diamonds have been sourced which are many thousand of carats in weight.