"Project Vesta is a project to remove carbon dioxide (CO2) from the atmosphere and oceans by accelerating the weathering of a type of rock called olivine. When olivine interacts with water and the CO2 dissolved in it, a chemical reaction (called weathering) occurs that creates a bicarbonate solution that marine animals like corals use in their shells. The CO2 remains locked in that form and eventually settles as sediment or turns to limestone rock on the sea floor."

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Griffioen, Jasper (2017): Enhanced weathering of olivine in seawater. The efficiency as revealed by thermodynamic scenario analysis. In The Science of the Total Environment 575, pp. 536–544. DOI: 10.1016/j.scitotenv.2016.09.008.

"This study aimed to characterise how olivine can weather in seawater, to elucidate the role of secondary precipitation and to ascertain the efficiency in terms of molar CO₂ removal per mole of olivine dissolution. Geochemical thermodynamic equilibrium modelling was used, which considered both the variable mineralogical composition of olivine and the kinds of secondary precipitates that may be formed. The advantage is that such an approach is independent from local or regional factors as temperature, related kinetics, mineralogy, etc. The results show that the efficiency falls when secondary precipitates are formed."

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Montserrat, Francesc; Renforth, Phil; Hartmann, Jens; Leermakers, Martine; Knops, Pol; Meysman, Filip J. R. (2017): Olivine Dissolution in Seawater: Implications for CO2 Sequestration through Enhanced Weathering in Coastal Environments. In Environ. Sci. Technol. DOI: 10.1021/acs.est.6b05942.

"Here, we present results from batch reaction experiments, in which forsteritic olivine was subjected to rotational agitation in different seawater media for periods of days to months. Olivine dissolution caused a significant increase in alkalinity of the seawater with a consequent DIC increase due to CO₂ invasion, thus confirming viability of the basic concept of enhanced silicate weathering."

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"Give them enough time and some rocks will munch carbon dioxide, removing it from the atmosphere. Now scientists are using computer models to explore the possibility of speeding up this natural weathering process by sprinkling rock granules in the oceans, as a way of removing carbon dioxide from the atmosphere faster and counteracting climate change."

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