Sri Lanka has been known for thousands of years as a plentiful source of fabulous gems. Ancient literature from around the world record the abundance, quality and size of the precious stones that have originated here and have adorned monarchs for millennia. The tradition continues. Fine rubies that mined here have been prized for their size and color. However, in contemporary times, the sapphires have become more prized and better associated with Sri Lanka. International trade in beautiful jewelry has flourished over the centuries too, continuing to adorn lovers of fine gems the world over. Traditional methods are still used with tools that have changed little over the centuries. The spectacular results however, confirm that modern Sri Lankans are still just as skilled as their ancestors. Geological activity many millions of years ago produced metamorphic rocks carrying gem quality mineral deposits. On the island of Sri Lanka, such rocks have been exposed at ground surface due to millions of years of natural weathering and erosion. Over 90% of the island’s surface is estimated to be potentially gem-bearing land. Of the five major areas of gem mining activity in Sri Lanka, Ratnapura (the "City of Gems"), south-west of the central hills, is the traditional centre. The gem cutting and finishing industry in Sri Lanka is reputed to be the fastest developing in the world with the highest international standards. The jewelry design and manufacturing trade is also flourishing as skilled artisans practice the techniques of their ancestors.
Origin of Gemstones Almost the whole island of Sri Lanka consists of Pre-Cambrian age crystalline rock. There are a few localized sedimentary deposits close to the north-west coast and at the northern tip of the island. Small deposits of much younger limestones, sandstones and mudstones can be found in the north-west and in the northernmost peninsula. Geological surveys have shown that the Pre-Cambrian rocks form three major rock types which were formed by aluminium-rich sediments collecting in the highland basin existing then. This mode of genesis has directly resulted in the high prevalence of aluminium-rich varieties of gem minerals such as corundum, chrysoberyl, spinel, garnet, beryl, tourmaline and topaz, etc in these rocks. Gem Mining All gem mining activity is controlled and supervised by the National Gem and Jewellery Authority of Sri Lanka. Different methods of mining are as follows. 1. Open Cast Mining (shallow deposits) 2. Mining by Pits/Shafts and Tunnels 3. Dredging of River Beds – Manual & Gravel Pump Extraction