— You can only carve such lines with a diamond cutter!
— You’re mistaken, my friend. Those slabs were eroded by soil acids, and people simply polished them…
— Can’t you imagine the patterns were etched by people using acid?
— Ha-ha-ha, you crack me up! Savages, children from almost the Stone Age, building a factory to produce acid!
Those, or something like them, were the conversations among scholars as they examined the stone slabs that served as currency for the inhabitants of the New Hebrides.
What was the reality? The patterns were indeed created with strong hydrochloric acid. They didn’t need a chemical plant or modern equipment. European scientists had underestimated the ingenuity of the New Hebrideans — they used a natural “acid factory”: the small dolium snail.
Guided by the skilled hand of its master, the snail crawled across the marble surface of the slab, burning the desired pattern into it.
