Natural vs Lab Grown Diamonds
A Miracle of Nature vs A Technological Wonder
Natural diamonds are famous for their age, forming millions to billions of years ago. Natural diamonds are formed deep within the Earth’s mantle through intense heat and pressure. They are mined from the earth and each one is a unique result of nature’s process, often containing tiny inclusions that serve as a natural fingerprint of its origin. Natural diamonds are valued not only for their beauty but also for their rarity and geologic history.
In contrast, laboratory-grown diamonds are young. With a variety of high-quality options in new colors at a reduced price point, the demand for laboratory-grown diamonds has risen in recent years. Like their natural counterparts, laboratory-grown diamonds have the same crystal structure, consisting of tightly bonded carbon atoms. This results in nearly the same chemical, optical and physical properties as natural diamonds. By eye, the difference can potentially be indistinguishable. However, they are separated by vastly different growth histories.
There are two main processes used to create laboratory-grown diamonds: High-Pressure, High-Temperature and Chemical Vapor Deposition.
High-Pressure, High-Temperature (HPHT): Mimicking some of the key conditions of diamond formation – a capsule containing a source of carbon and a mixture of metals is heated to temperatures of 1300-1600°C (2400-2900° F) under pressures of 5-6 GPa, the equivalent of a depth of 150-190 km (~90-120 miles) beneath the surface of the Earth. An HPHT press can also be used to treat diamond color. The size of the diamond depends on several parameters, including the time allowed for growth and the volume of the capsule.
Chemical Vapor Deposition: Dramatically different from natural growth, CVD occurs at near-vacuum pressure. Based on complex gas-phase chemical processes typically activated by microwaves, the resulting glowing plasma ball releases carbon-containing constituents that rain onto diamond seeds, crystallizing as a new diamond at temperatures of 700-1200 °C (~1300-2200 F). CVD growth ideally progresses layer-by-layer, with each subsequent layer replicating the crystal structure beneath, creating a cubic block of diamond. The eventual size of the diamond depends on the size of the diamond seeds and the time allowed for growth.
