The island of Sri Lanka, also known as "Ceylon" has a long heritage for gem-mining and trading that dates back some 2,000 years. Sri Lanka is a tropical island situated in the Indian Ocean, off the southeastern tip of India. Sri Lanka has earned its namesake as the "Island of Gems," or "Gem Island" (Ratna Dweepa), with its abundance of corundum gems, chrysoberyl and alexandrite, garnet, moonstone, peridot, spinel, topaz, tourmaline, and zircon.
During the 16th century, Portuguese explorer Vasco de Gama said of Sri Lanka: "Ceylon has all the fine cinnamon of the Indies and the best sapphires." The gem-trading center for Sri Lanka is the town of Ratnapura (Ratnapoora) which is Sinhalease for "Gem Town," located 100 kilometers southeast of the capital city of Colombo.
Gem Occurrences in Sri Lanka
Ceylon 'Pushparaga' *** pushparaga flower
Sri Lanka is perhaps best known for its fine sapphire. Sapphire from Sri Lanka occurs in a wide range of hues from orange-yellow (Padparadscha) to cornflower-blue ("Ceylon blue"), green, orange, pink, purple, yellow (pushparaga) and white sapphire. Sri Lanka's white "Geuda sapphire" is a semi-opaque milk-white stone that can be heated to a deep blue.
Padparadscha Sapphire from Sri Lanka
Sri Lanka is known for its Ceylon Blue, and padparadscha (aka padmaraga, pathmaraga) sapphire, named after the island's lotus flower, and its unique soft pastel orange-pink color. The name "Padparadscha" or "Pathmaraga" comes from the Sanskrit or Singhalese "padma raga" meaning "lotus blossom." The traditional mining areas of Ceylon were located in the vicinity of Ratnapura, about 100 kilometers south-east of the capital of Colombo.
Although padparadscha sapphire is synonymous with Sri Lanka, the use of the name is no longer limited to gems found in this single geographic region. The seven members of the Laboratory Manual Harmonization Committee (LMHC) now define padparadscha as a "variety of corundum from any geographical origin whose color is a subtle mixture of pinkish-orange to orangey-pink, with pastel tones and low to medium saturations"
Pushparaga Sapphire from Sri Lanka
Yellow sapphire from Sri Lanka is called "pushparaga" in Singhalese ("pukhraj" in Hindi), and can be comparable in value to the finest Mogok sapphire. Pushparaga, also known as "Oriental topaz" or "hyacinth" has a golden or honey yellow color withbrownish secondary hues.
Heat Treated Gem Material from Sri Lanka
Sri Lanka has a two thousand year history of heating their rubies to enhance the reddish-pink color, and remove any bluish or purplish hues. Sri Lanka's "burners" traditionally apply heat treatment using a blow-pipe and charcoal burner, to super-heat the stone.
The government has instituted a five-year program to increase Sri Lanka's share of the gem heat-treatment industry by advancing experimentation in heat-treatment technologies [3]. The Sri Lankan government is also opening up new lands to sapphire mining in the central part of the country.
It is a common sight to see vendors in Sri Lanka's Ratnapura's Newitigala 'morning gem market,' and Thailand's Muang Chan's (Chanthaburi's) 'weekend market' selling Sri Lankan sapphires alongside of material from Madagascar and Tanzania that was treated in Sri Lanka ("geuda sapphires"). African yellow sapphires are sometime sold as "Ceylon yellow," but can be distinguished by their distinct greenish-yellow hue.
Gem Mining in Sri Lanka
The government works in cooperation with land/farm owners to manage and allocate mining rights to their land in exchange for a percentage of the profit, should any gemstone be found on the property. The government sees to it that the land is not spoiled by mining operations, through strict regulation of low-impact mining proceedures.
Gem mining, or "gemming" in Sri Lanka is primarily from alluvial secondary deposits found in gem-bearing river gravels (illam), in ancient flood plains and streams that are now covered with productive farm land and terraced rice paddies. To access the gem-bearing gravel, 5 to 50 foot deep mining pits are hand-dug by teams of several workers, pumping out any ground-water as it enters the hole from below. When the pit is dug to the correct depth, tunnels are dug horizontally in several directions to minimize surface degradation.
Sluicing with conical-shaped baskets is used to extract the gems from the illam clay, gravel and sand slurry. The basket is swirled around until the heavier stones (Jathi) settle to the bottom of the basket.
The Ratnapura region was the first locality to mine sapphire on the island. Significant gem-mines throughout Sri Lanka are the Bibile sapphire mines (central), Elehara Gem Fields (near Ratnapura), Metiyagoda moonstone mines (south-west coastal), Morawaka (south-central), Nuwara Eliya mines (mountainous tea plantation area), and Pelmadulla sapphire mines (15 km south-east of Ratnapura).
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