How Strontium Titanate Shines Quite Unlike A Diamond
Strontium Titanate is not a material that most people know much about nowadays, but after the synthetic process that first produced it was first established in the 1940s, it enjoyed a brief – and literally sparkling – bit of fame.
The material has long been valued as a high-permittivity perovskite, with semiconductor and ferroelectric properties. But it gained some considerable attention in the 1950s and 60s when it was found it could be cut and shaped to resemble a diamond.
Not only was it clear and colourless like a diamond, but its capacity to reflect light across the spectrum and produce a wide range of colours, known as ‘fire’, exceeded that of a diamond. Several jewellery makers produced their own brands under names like Fabulite and Diagem.
This fame lasted up until the early 70s, but while the crystals were much cheaper than diamonds, by then the key flaw was evident as buyers saw increasing wear and tear. On the Mohs hardness scale, Strontium is only 5.5 compared with 10 for a diamond, with this relative softness being comparable to an opal, capable of being scratched with a sharp knife.
Strontium fell out of favour with jewellery wearers due to its softness as harder alternatives like Moissanite emerged, but it continues to make an impact in rather less obvious ways today, due to its conductivity. It has a role in high-voltage capacitors and voltage-dependent resistors.
Although it was initially produced synthetically as a combination of Strontium and Titanium, the material was discovered in naturally occurring form for the first time in 1982, with deposits in Siberia. Others have now been found around the world.
Companies using it today in electronic applications may consider it remarkable that today this is a material with very important uses, yet almost forgotten from the days when Strontium was the substitute of choice for diamonds.
