In his 1998 book, Molecules at an Exhibition, John Emsley described two elements as ‘from heaven’. One was titanium, first discovered in 1791 when William Gregor, the vicar of Creed in Cornwall and a keen geologist, went about collecting Cornish minerals. In Menaccan he found some black sand with unusual properties that clearly included something new. He wanted to name it menaccanine but a German chemist who discovered it again a few years later named it titanium and this name stuck. It turns out to be abundant in the earth’s crust though the pure metal was not isolated until 1910. Since then its uses have multiplied. I once worked in a laboratory and we used titanium tetrachloride as a catalyst in making plastics. The most common use of titanium is titanium dioxide which gives a brilliant white to paint and such other products as window frames. The metal itself is light, strong and not easily corroded. It is often alloyed with other metals with many uses in engineering (spacecraft, aircraft, cars...) but many people will know its medical application in replacement hip joints where it does not react with body tissues. Altogether titanium has turned out to be an extremely useful substance.
Now why does John Emsley describe it as coming from heaven? I couldn’t see why from his book but most other elements could be described as ‘from heaven’. As far as we understand things it works like this. Stars are great nuclear reactors which burn hydrogen and produce helium but all the elements needed for life were not found in the first generation of stars until late in their life and were not released until some of them departed in a great explosion. As later generations of stars were formed from clouds of gas they took in the debris from dead stars. We were fortunate that when the planets formed around our sun so many elements gravitated together to form our earth which is rich in substances that support life as well as many, such as titanium, that are plain useful. They are ‘from heaven’ in the sense that they come from the stars. It is very wonderful.
