Achieving the blackest of blacks has been one of humanity’s enduring challenges. It is a frontier that unites modern nanotechnologists with nature’s ancient colour palette.

Black emerged as one of humanity’s first engineered colours, stemming from charcoal and soot used in the prehistoric cave art of Lascaux in southwestern France.

For centuries, darkness has been associated with power, rarity and prestige. In Renaissance Europe, richly dyed black fabrics became symbols of wealth and authority, adorning monarchs, judges and aristocrats. Black conveyed status because producing a deep, uniform darkness was technically demanding and prohibitively expensive.

But the pursuit of ever-deeper black is more than just an aesthetic endeavour. At the turn of the 20th century, German theoretical physicist Max Planck sought to explain the mystery of blackbody radiation – and revealed fundamental laws governing the interaction of light and matter.

While Planck examined the theoretical behaviour of an ideal perfect absorber, today’s scientists have demonstrated materials that come astonishingly close to this in practice. Advances in nanotechnology – engineering at an atomic and molecular scale – have enabled the creation of ultra-black materials capable of absorbing virtually the entire spectrum of visible light. (The more light that is absorbed, the darker the black appears.)

One commercial example was BMW’s ultra-black concept car. Coated in “Vantablack”, a material composed of........

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