OLIVINE: A New Market

The cement industry produces 8% of global CO2 emissions. CBAM (Carbon Border Adjustment Mechanism), the EU's initiative to tax embodied carbon is set to come into Europe by 2026 and into the UK by 2027. But what if hard to abate industries could decarbonise using some of the world's most abundant alternative materials? Olivine, a little known mineral, might hold the key to reducing CO2 emissions by the gigaton.

By Natasha Higgins

4/29/20245 min read

Spanning the northern coast of Oman, a country famous for its mountain ranges and rugged coastline, sits a large ancient geological formation - The Samail Ophiolite - an oceanic crust with a 3 – 8 km thick sequence of ultramafic rock, formed 95 million years ago.  

“The Samail Ophiolite is one of the best exposed ophiolites in the world,” explains Juerg Matter, Professor of Geoengineering and Carbon Management and the University of Southampton. Stretching 350 km in length and 40 km wide, it’s thought to be the largest inferred mineral resource of olivine – a silicate mineral estimated to cover 50 to 70 percent of the Earth’s upper mantle which could potentially capture a vast amount of the world’s CO2.

Matter first travelled to Oman in the late nineties when he was working on ground water resources in arid areas. He later returned while working on Carbon Capture and Storage at Columbia University studying the natural carbonation and mineralisation of peridotite, an ultramafic rock that contains a minimum of 40% olivine: “For many years, my colleague Prof. Peter Keleman, a geologist at Columbia University’s Lamont-Doherty Earth Observatory and I, studied the natural uptake and interaction of these rocks with water and CO2 and found there to be extensive carbonation”.

It was around 2006 that the scientific community began taking an interest in CO2 absorption from ultramafic rocks, believes Sobhi Nasir, Director of the Earth Sciences Research Centre at Sultan Qaboos University in Muscat. “It was becoming clear that olivine and other magnesium silicate minerals had the unique ability to sequester large amounts of CO2 and interest was coming in from scientists worldwide”.

Today, the idea of commercialising olivine in its application to reduce CO2 emissions is widespread. As interest continues to grow, research shows an estimated 120 trillion tonnes of olivine in the Samail Ophiolite, a figure backed up by the Minerals Development Oman (MDO). They are quick to state, however, that this resource needs more exploration, and they are in the process of collecting samples from 12 different locations for testing.

“We expect these samples to be homogeneous with the 43% MgO olivine we have in Oman,” explains MDO Geologist, Faris Shukairi, “Going forwards, the key is getting the logistics in place to start mining it commercially”.

Andrew Simeonidis, Global Product Manager of Olivine at Sibelco, which operates the world’s largest commercialised olivine mine in Norway, echoes this point: “Although there are numerous olivine deposits around the world that can be scaled up to remove CO2 from the atmosphere at gigaton scale with olivine reserves estimated at billions of tonnes and potential resources in hundreds of billions of tonnes, logistics are the key cost area.

“The number of handling points for loading, unloading and storage, the size of the shipments, the last mile distribution and deployment, all contribute significantly to the total cost of delivery.

“The mode of transportation holds significant importance due to its impact on efficiency, cost, accessibility, environmental considerations, and overall supply chain performance. For olivine to be scaled up globally for CO2 reduction applications, this is the key area that requires focus”.

Simeonidis further points out that olivine open pit mines can be replicated and scaled in different geographies with similar cost structures from extracting the mineral to field deployment. Well-located deposits and low CO2 extraction, processing and logistics have a positive effect on the CDR ratio. Aheim with its high-quality ore, favourable seashore location and a low CO2 electricity, qualifies as (one of) the best CDR (Carbon Dioxide Reductions) ratios for ERW (Enhanced Rock Weathering).

The way Sibelco works to extract olivine from the earth’s crust is by drilling, blasting and crushing. A single blast (used to break up the rocks) removes up to 40,000 tonnes of olivine. The site is predominantly powered by hydroelectricity and boasts a 4km conveyor system for transport which limits the need for heavy vehicles or double-handling of materials in a bid to reduce emissions.

After blasting, the olivine is put into a crusher before being loaded onto the conveyor to a processing and storage facility. At the processing plant it is crushed further and screened into undried and dried products depending on the end application.

As it happens, according to Sibelco, there is already a significant amount of olivine ready for commercial use across the world. Significant deposits in operational use can be found in Europe, Central and Northern America, Asia Pacific and elsewhere priced at around $17 per tonne.  New entrants and greenfield sites are being explored in Greenland, New Zealand and Albania.

According to the MDO, Oman itself has around 2m tonnes of olivine readily available as a by-product from its chromite mines in the port town of Sohar - meaning the logistics are in place to start shipping it out.  “They have a problem because they don’t know what to do with the olivine,” says Nasir.

Race to Zero

As the world moves towards its goal of reaching Net Zero, Matter rightly points out that we make 40 billion tonnes of CO2 a year “and we need lots of solutions”. Vesta, for example, a US based startup, is using olivine for Coastal Carbon Capture to reduce ocean acidity and remove carbon dioxide from the atmosphere. Another company which removes CO2 permanently by mineralising it in peridotite is 44.01, of which Matter is co-founder. And there’s Seratech, an Imperial College spin-out, using olivine to decarbonise cement, responsible for 8% of global CO2 emissions, in a process that transforms industrial CO2 into next-generation building materials, cutting emissions by up to 95%.

Later this year Seratech will be looking to build its first small scale pilot facility for verification of the process: “We’ll run that for two years and by 2027 we’ll have our first full scale industrial facility. After this the plan is to expand as fast as possible and really make a dent in CO2 emissions. If we can licence this technology to major industrial players who already have the capital to invest, then we can make a real impact much faster,” say Sam Draper, Seratech CEO.

Good news, according to Nasir, is that in Oman the government is encouraging projects and research into reducing CO2 emissions. “It’s very easy to invest in Oman – The Ministry of Energy and Minerals will provide help for producing and licensing these rocks. They want to make use of our mineral industry and are looking for anything other than fossil fuels”.  

So, where does that leave olivine and does this new market truly hold one of the keys to combatting the climate crisis? Maja Bar Rasmussen, a post-doctoral researcher in the department of Geosciences and Natural Resource Management at the University of Copenhagen, is working with ultramafic rocks from Greenland and testing their potential to act as a means for carbon capture.  

“Olivine certainly has great potential to capture a large amount of the world’s CO2. Not only is it hugely abundant but is relatively easy to get hold of.

“Lots of research for different mechanisms for CCU and storage using olivine is taking place. It’s an emerging market and if people are smart, they’ll make money as more and more businesses realise the need to mitigate climate emissions.  

“Of course, work needs to go into optimising the logistics of transport and the processing of olivine to make it more sustainable. As with any new material it’s a mathematical question: How much do you emit versus how much do you capture?

“Naturally, there is still hesitancy with people saying, ‘we need to figure out this process completely’. From a scientific perspective I completely agree but at the same time we should not shy away from taking big steps. Some of those big steps are being taken by startups but I think we need to be even more brave in embracing any climate mitigation solution that holds promise”.

Ophiolite Mountains, Oman. Image credit: Shutterstock