A recent experiment showed one application of olivine can release enough nickel to contaminate soil for hundreds of years. This limits olivine’s use to very low application rates that will still release nickel but limit the amount of CO2 Olivine can capture. Despite the potential of olivine for carbon sequestration in soil and oceans, the high levels of nickel are a significant drawback that is difficult to mitigate, greatly reducing olivine’s potential as a carbon capture solution in the near future.
Luckily, wollastonite is very clean and can be applied annually to the soil. The study below compares wollastonite with a wide variety of minerals for its capacity to sequester carbon dioxide and the amount of nickel released into the soil.