The recent announcement by British Titanium that it is developing technology to produce oxygen on the moon sounds like science fiction, but it is based on a new titanium extraction process developed by Derek Fray from the University of Cambridge ( If this venture is successful, we will be seeing and hearing a great deal more of the sibling materials titanium and titania, related through oxidation, who, like tennis stars the Williams sisters, rival each other in beauty and ability.

Titania is the elder of the two, having been discovered in the late 18th century. She was always the arty one, finding use as the most brilliant white pigment in painting and cosmetics. Titanium arrived on the scene a hundred or so years later and, as is often the case with younger brothers, was almost immediately hailed as genius material. As strong as steel but with roughly half the density and virtually immune to environmental attack of any sort, titanium was a prodigy and soon found employment in jet engines. It was so important to the space race that both the Soviets and the Americans built whole industries around it. The metal became a symbol of their technical rivalry and each country erected a statue to the material. The American tribute was the General Motors Firebird II titanium car. Basically a jet engine on wheels, the Firebird II was an automotive manifesto for the power of new materials to win individual freedom. Wonderful as the Firebird II was, it was no match for the Russian sculpture Conquest of Cosmos, which depicts a rocket screaming into the atmosphere. The rocket and its two hundred feet of exhaust gases are sculpted in solid titanium, an extravagance that only a superpower could afford, an expression both of the mastery of this most exotic material and of the communist ambition to master space travel. Thus titanium became, like the Tyrian purple pigment of ancient Rome, a symbol of imperial power.

After the cold war, when the magic of flying was replaced by the magic of duty-free goods, titanium lost its rock star status. Its sister titania on the other hand, was found to have remarkable aesthetic virtues. It was discovered to have a photocatalytic surface, which means that under ultraviolet light it produces an electron and hole pair. These behave like free radicals, which destroy and decompose any organic molecules or biological cells in contact with the surface. The upshot of this is that titania surfaces are self-cleaning, antibacterial, and antiviral. Recently, this research has yielded self-cleaning glass, antibacterial wall tiles, and the first self-cleaning buildings constructed using concrete enriched with titania, such as the Dives in Misericordia Church in Rome.

Since the end of the space race, titanium has led a much humbler existence, being used for bicycles, golf clubs, horseshoes, exhaust systems, hip replacements, and other general earth-bound tasks. It can be colored through anodization, an unfortunate discovery that has spawned the most appalling art form where noble titanium is anodized and etched in splodgy multicoloured patterns and then placed on unsuspecting gallery walls or made into terrible jewelry, which disguises its true titanic nature.

In the 1990s, titanium was discovered by architects. Its outstanding physical properties, which include an aesthetic nobility – a natural ethereal hue that, like the sea, changes mysteriously from green to blue depending on the light – catapulted it, Travolta-like, back into the limelight. Frank Gery's titanium-clad Guggenheim Museum in Bilbao was titanium's Pulp Fiction, its spaceship-like design a reminder of the material's Sputnik heritage.

Titanium is now back as a superstar material, featuring in all the world's most avant-garde buildings. It is also at the forefront of body architecture, being hypoallergenic, tough, and beautiful – thus an ideal material for body piercings. Of course, titanium would be nothing without its superb corrosion resistance properties. These are the result of its oxide coating, a protective embrace from Shakespeare's queen of the fairies, Titania.

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DOI: 10.1016/S1369-7021(05)00773-X