It seems that basalt consists mainly of metal oxides, predominantly Fe, Ca, Mg and Al. How does carbonic acid from rain get bound into basalt, without dissolving in the next rainstorm?
(My knowledge of chemistry is restricted to "A" level, what Americans would call High School; and I've forgotten it all, because it was 40 years ago).
The article says that basalts weather down into clays, which aren't carbonates.
To reach maximum sequestration rate I thought it was much longer than that (~95% within 30 years at 3um). Where did you get your numbers from (curious, always looking for more sources)?
I didn't notice any mention of how long it takes powdered basalt to weather down. Is that over a year?