Confused about Natural Diamond vs Lab-Grown?

You’re not alone. There has been considerable conflicting and deliberate mis-information in the public domain about the differences between natural  and synethetic (man made) diamonds, so it is unsurprising that consumers lack clarity. This blog will clarify the characteristics they share, the differences between them, how they are priced, how to identify them, and what to consider when purchasing diamonds.

Natural Diamonds

Natural diamonds formed under extreme heat (≿900°C ) and pressure billions of years ago deep in the mantle of the earth. At about 120km beneath the earth’s crust, diamond is the stable and preferred crystal structure of carbon. Conversely, the preferred state of carbon at the surface of the earth, where conditions are extremely different, is graphite. The only reason we have access to diamonds is due to historic volcanic eruptions.

Diamonds were captured by chance as magma surged towards the surface of the earth. The diamonds had to be transported to the surface incredibly quickly to avoid a transition in form and structure from diamond to graphite.

natural diamond vs lab grown

The mining and recovery of natural diamonds involves accessing primary and secondary deposits. Primary deposits are kimberlite pipes, which are the vertical channels of (sometimes) diamond-containing-magma. Over millions of years, much of this earth has eroded and been washed into rivers, gravel pits and the ocean. These are known as secondary deposits of diamond, and usually contain very good quality natural diamonds as they have withstood extreme exposure and punishment over long periods of time.

Only a tiny proportion of natural diamonds which are recovered from source are gem quality. They are genuinly rare and have evolved naturally in the mantle of the earth.

natural diamond vs lab grown

Laboratory Grown Diamonds

Lab grown (or synthetic) diamonds are diamonds which have been created by man. Lab grown diamonds are real diamonds which share the same composition and structure as natural diamonds. They therefore have the same physical and optical properties. In order to synthesize a diamond, the same extreme heat and pressure conditions need to be created as when a natural diamond evolves.

The most common ways to synthesize a diamond include High Pressure High Temperature (HPHT) and Chemical Vapour Deposition (CVD).

HPHT replicates the conditions in which a natural diamond evolves. It requires a carbon source, extremely high pressure between 50 – 80Kb and temperatures between 1350 – 1600°C.

CVD diamonds are produced at lower temperatures using microwave technology and methane to produce a plasma to encourage synthetic growth of diamonds.

Due to the secrecy surrounding the manufacture, location, energy sources and opacity of ownership, it is difficult to develop informed judgements on the process.

Pricing of Natural Diamonds vs Lab Grown Diamonds

Price takes several factors into account including carat (weight), colour, (quality of) cut  and clarity. Furthermore, there are various price sensitive points where the price per carat (ppc) will jump. Most importantly, like all precious objects, including fine art, the market is defined by rarity.

As gem quality natural diamonds are genuinely rare, they command a substantially greater price than mass produced lab grown diamonds. There is nothing rare about a lab grown diamond- and never will be. This has two ramifications on price:


  1. At the time of writing, the price of newly created lab grown diamonds is somewhere between 30-50% less than their comparable natural counterparts.
  2. There is virtually no value for second hand lab grown diamonds. There is no demand and very little value.

How to tell the difference between a natural diamond and a lab grown diamond

As both natural diamonds and lab grown diamonds are both diamonds, it is impossible to distinguish between them without specialist equipment. Unfortunately small lab grown diamonds have entered the supply chain of natural diamonds without disclosure, so it is essential that diamonds are tested with specialist equipment to identify any rogue stones and defend the integrity of the supply chain.

The London Diamond Bourse has equipment available to undertake such testing.

natural diamonds vs lab grown

Is a natural diamond or lab grown diamond more “ethical”?

This is a hot potato of a topic with many complex issues. Even the term “ethical” means different things to different people. There is no simple answer. Let’s explore each in turn.

Governments of most diamond producing countries in Africa are typically party to the ownership structure of any diamond mining enterprise. This allows them to exert influence over policy, repatriation of skills, training, employment, receive export revenue and enforce reinstatement of terrain at the conclusion of the life of an open pit mine. It also ensures that diamond revenues contribute to the growth of the nation, developing infracture including schools, roads, hospitals and housing. It has been said that the sale of natural diamonds has educated a generation of Botswanians.

Historic issues of conflict diamonds (those sold to fund armed warfare) have effectively been addressed via the Kimberley Process. However, consideration should be given to the impact on the environment of large scale open pit mining, and NGOs (Human Watch) often report pressure and harassment exercised on local villagers to leave areas surrounding diamond rich leases, and contamination of local water supply due to the tailings from mining activity. It should be stressed that this is usually in less developed diamond bearing countries which are less regulated and not operating as a joint venture with experienced and responsible miners.

There is little empirical data available which confirms the view that laboratory grown diamonds are “ethical”. Nor that they are harvested in a laboratory… In fact there is very little reliable independent data available at all.

Due to the secrecy surrounding their manufacture, usually in countries like Russia and China which have poor human rights records. Furthermore, according to a recent article by Bob Bares (, “Chinese diamond growers are often connected to the coutnry’s military”. This would counter any views that lab grown diamonds synthesized in China are conflict free.

It is not clear what the carbon footprint of creating synthetic diamonds is. Claims that CVD diamonds are carbon neutral have not been substantiated and are largely achieved by carbon offsetting.

Ownership structure is often opaque. But there is indisputably no benefit socially or economically to communities local to lab grown diamond production nor much in the way of employment.

How to choose between a natural diamond and lab grown diamond?

There are several things to consider:

  1. Properties: both natural and synthetic diamonds are real diamonds. They both share the same magnificent physical and optical properties.
  2. Price: as lab grown diamonds are mass produced, they have no rarity value so will always be cheaper. They have no secondary value. They continue to drop in value.
  3. Ethics: natural diamonds have far reaching and long standing benefits to the local community. This includes employment and large scale development of key infrastucture.It is understood that lab grown diamonds are produced in countries with questionable human rights records and have yet to substantiate their carbon footprint record. Given the enormous energy requirements of the synthetic diamond process, unless there is proof that renewable energy has been used, the carbon footprint will be poor.

In summary, general consensus is that if you are celebrating a key personal occasion such as an engagement, significant wedding anniversary or birthday, that the investment in natural diamonds is the default choice. The rareness of the stones acknowledges the significance of the occasion. The pieces inevitably become treasured heirlooms and have genuine secondary value.

For pieces of jewellery which may not be ordinarily affordable, the availability of lab grown diamonds presents opportunity. Just be aware that in the event of a subsequent sale, there may be little or no interest, and the value attributed to it will be a fraction of the original price.