Recently, the “world’s largest star sapphire cluster” was found in a garden in Sri Lanka. What is a star sapphire and why is the latest discovery significant? Let’s find out.
Where it was found
The huge rock was stumbled upon by labourers while digging a well in the backyard of a gem trader’s house in Kahawatte in Ratnapura district, a gem-rich area in Sri Lanka. The exact location is kept under wraps for security reasons. Pale blue in colour, the sapphire cluster weighs around 510 kg or 2.5 million carats. It has an estimated value of over $100 million in the international market. Discovered by accident, it has been aptly named “Serendipity Sapphire”.
Though the rock was discovered last year, announcement of the find was made just a few months ago. After the gem trader, who goes by the name Gamage, secretly informed authorities about the discovery, the stone was cleared of mud and other impurities before being analysed and certified by experts. It is said that during cleaning some stones fell out of the cluster and they were found to be high-quality star sapphires. However, experts have said that though the rock’s carat value is very high, all stones in the cluster may not be of high quality.
Ratnapura, which is Sinhalese for “city of gems”, is known as the gem capital of Sri Lanka. The place has yielded several valuable stones earlier. Sri Lanka is a leading exporter of sapphires and other precious stones. The latest discovery is expected to give a boost to the country’s gem industry.
What is a star sapphire?
A star sapphire is a type of sapphire that displays a star-like phenomenon known as asterism. It contains intersecting needle-like mineral inclusions that form a star-shaped pattern when viewed under light. Like diamonds, sapphire is a precious stone. Although blue is the best-known colour of sapphire, it can be found in other colours too such as grey and black, and sometimes without colour.
How do sapphires form?
Sapphire is one of the two primary gem varieties (the other being ruby) of the mineral corundum. Corundum is an extremely hard form of aluminium oxide, which forms deep in the Earth’s crust under extreme heat and intense pressure over a long period of time. Pushed to the surface by volcanic eruptions, corundum is found in igneous rocks that form when hot magma exits and hardens. The presence of metal impurities in it is responsible for its different shades. The blue sapphire is created as a result of titanium being present within the conundum rock. Did you know corundum is the hardest-known natural substance after diamond?
Many of the largest sapphires discovered have been star sapphires and they are used in crafting jewellery. High-quality sapphire deposits are found in Sri Lanka, India (Kashmir), China Africa, and Madagascar.
Picture Credit : Google
