Deep pit mining remains one of the most iconic and labor-intensive methods used in Sri Lankan sapphire extraction. Vertical rectangular pits — often reinforced with timber such as rubber wood, coconut or areca nut — are dug through soil and gravel until gem-bearing layers are reached. Each stage of excavation is carefully sorted to ensure no Ceylon sapphire is missed.

While traditional materials are still used, many modern deep mines incorporate steel plates and powered water pumps to prevent flooding and increase safety. Digging continues until miners locate the precious gemstone layer, where natural Sri Lankan sapphires and other valuable gems have formed over millions of years.

This method is respected for its precision and is commonly used in areas rich with Ceylon blue sapphire, making Sri Lanka one of the world’s most trusted sources of high-quality gemstones.