Sustainability – the biogenic birth of oolitic aragonite sand

The biogenic nature of this unique mineral not only improves the environment through its ability to naturally renew, but it also sequesters CO2 from the atmosphere, while greatly minimizing the overall carbon footprint of finished products. Oolitic aragonite is the only naturally renewable source of high purity calcium carbonate that has a negative carbon footprint. In addition to providing sustainability benefits, it also has performance benefits for a variety of different industries. It is also approved for use in organic production in accordance with the USDA National Organic Standards.  

Naturally Renewable 

The formation of oolitic aragonite (biogenic CaCO3) occurs as a phenomenon described as a “Whitings” event.  The “Whitings” are an accumulation of precipitated calcium carbonate induced by photosynthesis, occurring in blooms of phytoplankton, which seasonally enter the warm shallow waters of the Bahamas. Within our 500 sq. mi. harvesting areas, roughly 2 million tons of oolitic aragonite is generated each year. ASTM D6866 testing confirms the renewability of oolitic aragonite and its biobased origins. Ground calcium carbonate (limestone etc.) is from nonrenewable fossil sources, whereas oolitic aragonite is the only calcium carbonate from a renewable and sustainable source.

Carbon Sequestration 

Oolitic Aragonite naturally sequesters carbon during its formation. It is generated through the mineralization of Carbon Dioxide (CO2) to Calcium Carbonate (CaCO3) within natural occurring Blooms of phytoplankton, further picoplankton: specifically Cyanobacteria and unicellular blue-green algae. During this process, carbon from the atmosphere is removed and binds with Calcium in the water, precipitating calcium carbonate.

Photosynthesis drives the engine of both forms of carbon sequestration by cyanobacteria:

  1. Reducing CO2 to organic compounds at the same time producing Oxygen (O2) through the Calvin-Benson-Bassham cycle.

  2. Mineralizing CO2 to recalcitrant carbonates; Calcium Carbonate (CaCO3).

Cyanobacteria has a Carbon Dioxide Concentrating Mechanism (CCM), a biochemical system that allows the cells to raise the concentration of CO2 at the site of the carboxylating enzyme rubulose (RUBISCO) up to 1,000 times surrounding medium.  Cyanobacteria excretes organic polymeric substances to form extracellular formations. These Exopolymeric substances (EPS) serve as a nucleation surface for mineralization.

Negative Carbon Footprint

Oolitic aragonite sequesters carbon during its formation. Our third party verified Carbon Footprint Analysis showed that oolitic aragonite has a negative carbon footprint, meaning aragonite removes more carbon from the atmosphere than is emitted by the harvesting. The use of oolitic aragonite can potentially help to reduce the carbon footprint of products it is used in, helping you to reach your sustainability goals.

Results of the ISO 14067:2018 Carbon Footprint Study for Oolitic Aragonite

Calcean conducted a third-party verified life cycle analysis and a partial carbon footprint study of the oolitic aragonite. As a result, the total carbon composition of the raw material, by factoring the total amount of carbon to calcium in aragonite composition, stored an amount of carbon greater than the amount used to extract the raw material. This methodology is in alignment with the guidance of ISO 14067:2018 Greenhouse gases — Carbon footprint of products — Requirements and guidelines for quantification, which states:

“In the LCIA phase of a CFP study, the potential climate change impact of each GHG emitted and removed by the product system shall be calculated by multiplying the mass of GHG released or removed by the 100-year GWP given by the IPCC in units of kg CO2e per kg emission (with carbon feedbacks, according to IPCC).”

This means the raw material has a net negative carbon footprint when considering its extraction and storage of biogenic carbon.  

This Carbon Footprint of a Product study is a partial study based on a cradle to gate life cycle analysis of the harvesting of oolitic aragonite by Sandy Cay Development in GBB. The negative carbon footprint is strongly dependent on the product's life cycle and its subsequent end-of-life scenario. Because oolitic aragonite can be a raw material input to any number of products, there is the possibility of chemical reactions that lead to the release of the carbon from the aragonite as CO2 is emitted back to the atmosphere. Therefore, manufacturers using oolitic aragonite as raw material should independently calculate the Carbon Footprint of their products. This Carbon Footprint claim is of raw material only (as sold by Calcean) and does not mean that a product made from oolitic aragonite can have a total negative carbon footprint for the entire product. 

Additional Studies

We have also conducted a third party verified Life Cycle Analysis and ASTM D6866 Biobased Content studies. Please contact us to learn more about how this data can help your business in its sustainability efforts.