Is Growing Diamonds a Sustainable Alternative to Diamond Mining?

What Does Sustainability Mean?

Although there's no official definition for sustainability, it generally refers to the use of a resource in a responsible manner.

By any definition, diamond mining isn't considered sustainable. There's a limited amount of this material in the Earth. Mining at current rates will one day deplete this resource. On the other hand, lab-created diamonds are far less limited. The ingredients for producing diamonds through both high pressure/high temperature (HPHT) and chemical vapor deposition (CVD) processes are available in much greater quantities. People will run out of natural diamonds in the Earth long before they exhaust materials for synthesizing diamonds.

There's more to responsible use, however. Producing diamonds in a lab is also far less damaging to ecosystems, wildlife, and human populations than mining diamonds. Most dramatically, lab-diamonds have less of an impact on their immediate surroundings than mined diamonds.

For these reasons, companies market lab-grown diamonds as a sustainable alternative to mined diamonds. However, the environmental impact of manufacturing diamonds isn't negligible, either. We'll examine its impact more closely later. First, let's examine diamond mining methods and their environmental impact.

How are Diamonds Mined?

A variety of methods are used for mining diamonds. Each has its own harmful environmental impact. People mine primary deposits through two main methods: open-pit mining and underground mining. Recently, marine mining has become more common.

Open-Pit Diamond Mining

Open-pit diamond mining requires digging large pits up to hundreds of meters deep. This process removes millions of years worth of sediments deposited after the diamonds were first formed. It also displaces hundreds of acres of earth, which can devastate the natural environment and disrupt fragile ecosystems, causing irreversible damage.

Underground Diamond Mining

Underground mining usually occurs when an open-pit mine has been depleted or when the diamonds are located too deep below the surface to reach via an open pit. This process costs far more than open-pit mining.

Marine Diamond Mining

Marine diamond mining is used to retrieve diamonds deposited in marine environments. In this process, after scouting the location, large vessels with dredges remove sediment from the ocean floor. The sediment is then sorted on the ship, where the diamonds are removed and the excess sediment is then returned to the ocean floor.

The Environmental Impact of Diamond Mining

Energy and Carbon Emissions

On average, mining companies move 250 tons of earth per carat of mined diamond. Moving so much material requires substantial amounts of energy, which usually comes from fossil fuels. Their use releases carbon and other greenhouse gases into the atmosphere. In addition, maintaining these expansive facilities also requires energy.

On average, 160 kg of greenhouse gases is released per polished carat of mined diamond.

Impact on Ecosystems

Diamond mining disturbs a large area around its site, which can greatly harm local ecosystems by polluting the soil and water supplies. For example, hundreds of cattle died after drinking water from the Odzi River in Zimbabwe, located downstream from a diamond processing plant. Similar incidents occur throughout mining regions in Africa with limited water supplies. Local people, livestock, and wildlife have no choice but to drink contaminated water.

Impact on Oceans

Companies that operate marine diamond mining vessels contend that the natural environment will recover once mining operations finish. Although most of the sediment removed during mining is returned, this process can take two to ten years. The long-term consequences of marine mining are still unknown, since this is a relatively new practice. Many environmentalists also remain concerned by the impact of noise, machinery, and light on marine life, in addition to the challenges already posed by pollution and climate change.

Efforts to Improve Diamond Mining Techniques

Many companies are working to improve their diamond mining techniques, and a host of environmental regulations are also in place to protect mining regions. However, accidents and violations of regulations still happen. 

Ultimately, natural diamonds come from hundreds of meters underground. The ecological disturbances and energy required to reach this non-renewable resource make truly sustainable diamond mining impossible.

How Does Diamond Synthesis Compare to Mining?

Opting for lab-grown diamonds will avoid perpetuating the environmental harm diamond mining can create. Synthetic diamonds don't require the same disruptive mining techniques. However, lab-grown diamonds have an environmental impact, too. They're less sustainable than their marketing may suggest.

Energy and Carbon Emissions of Lab-Grown Diamonds

Recreating the high pressure and temperature conditions found underground requires a great amount of energy and resources. Both HPHT and CVD involve reaching temperatures over 800º C and pressures up to 70,000 atm. Usually, the energy to accomplish this comes from fossil and other non-renewable fuels.

On average, producing one polished carat of lab-grown diamond releases 511 kg of greenhouse gases, more than three times that of one polished carat of mined diamond. To put this into perspective, the typical US household produces 48 metric tons (48,000 kg) of greenhouse gases each year.

Environmental Impact of Lab-Grown Diamonds

The environmental impact of lab-grown diamonds varies, depending on the local regulations in place and the policies of the producers. For example, Diamond Foundry produces lab-grown diamonds using solar power. This reduces the emissions and environmental impact of their stones.

Most lab-grown diamond manufacturers don't use renewable energy sources. However, researchers constantly look for improvements not only to the quality of synthetic stones but also to their production methods. Thus, there is potential for truly sustainable lab-grown diamonds in the future.