The Science of Sapphire

The “Star of Adam”, found in a mine in Sri Lanka, is believed to be the biggest sapphire ever discovered. It weighs in at over 1,404 carats, that’s around 280g or just under ten ounces. But what do we know about the formation of this remarkable gemstone – and how could it grow so huge?

Sapphire is a bright blue gem mineral and a form of corundum (aluminium oxide), the hard gritty stuff used as an abrasive in emery paper. It is incredibly hard – a fact important in understanding its occurrence in places like the Sri Lankan mines.

Sapphire is a type of “dirty” corundum. If you add just a trace of iron and titanium to the mixture of aluminium and oxygen from which the corundum is growing, it forms as sapphire. (If you add chromium to the corundum as it grows then you will get a ruby – Sri Lanka is also famous for its rubies).

At Goldcraft, we offer a wide ranger of jewellery made from gemstones, as well as being able to make bespoke jewellery using any materials you wish. Simply follow the link on our homepage for a free quote today. 

The Goldcraft Team