The distinct hexagonal columns found at Kiama’s Bombo Headland Quarry on the New South Wales south coast, like those of the Giant’s Causeway in Ireland, are a natural phenomenon offering geologists insights into the Earth’s core mantle.
But they also tell a different story, one of hard-working men doing loud and dangerous mining work as old Sydney town established itself on the back of basalt.
Aboriginal and Torres Strait Islander readers are advised this story has a photo of people who have died.
First mined in the 1880s, basalt came to be known as Kiama’s blue diamond.
“Kiama’s blue diamond

