Carbonates may remain exposed to the atmosphere or be buried over time depending on the location and approach. A portion of exposed and buried carbonates may undergo weathering over time. If and when carbonates weather, there is an additional shift in CO₂ fluxes as a result of introducing alkalinity to the system and storing additional CO₂ as bicarbonate. This process approximately doubles the associated CO₂ storage. Although most carbonates will ultimately weather, this process should only be credited when the impact on atmospheric CO₂ actually occurs and must take into account the full suite of uncertainties related to quantifying weathering outcomes (see the Enhanced Weathering pathway). In the absence of clear measurement of carbonate weathering, we recommend alkaline waste mineralization approaches only consider and credit the mineral phase of CO₂ storage.