What is a major source of black star sapphire?

Australia is recognized as a major source of black star sapphire, which is renowned for its unique appearance characterized by a star-like phenomenon, also known as asterism. This effect occurs due to the alignment of fibrous inclusions within the stone, which reflects light in a way that creates a star pattern visible on the surface.

Australian black star sapphires are particularly valued for their deep coloration and well-defined stars, making them sought-after by collectors and the jewelry market. The geological conditions in Australia are conducive to the formation of high-quality sapphires, which contributes to the country's reputation in gemstone production. Other regions may produce sapphires, but Australia is primarily associated with the exceptional quality of black star sapphires.