basalt

The worst affected are the basalt columns that make up The Loom – 10 ft high leaning towers of rock.

“This is a fresh basalt here,” says Dr Voight, showing me a lump of black rock taken from a recent volcanic eruption, and riddled with tiny holes.

One such approach, called enhanced rock weathering, involves spreading finely ground silicate rocks, like basalt, on the ground or the ocean, which absorb carbon dioxide from the air as they weather in the rain.

On Earth, basalts are a main component of the planet's crust, especially under the oceans, while olivines are abundant in its mantle.

An enormous basalt cascading fountain engineered to appear like the rippling surface of water echoes the constantly moving tides and chop of nearby Elliott Bay.