Sri Lanka´s gem - Anuradhapura
Sri Lanka Sapphire & Ruby Mining Locations
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 'Gem Island' or 'Island of Gems' (Ratna Dweepa), with its abundance of corundum gems, chrysoberyl and alexandrite, garnet, moonstone, peridot, spinel, topaz, tourmaline, and zircon.
Ancient mariners celebrated the gems of "Taprobane," and their expeditions fueled the story-tellers of the Arabian Nights and their fables of the jewels of "Serendib." During the Middle Ages, travelers told of the "sapphires, topazes, amethysts, garnets, and other costly stones" of Ceylon, and of the ruby which belonged to the Kandyan king of Serendib, having "a span in length, without a flaw, and brilliant beyond description".
Corundum forms a minor component of a number of metamorphic rocks, marbles and schists, but also of granite, pegmatite, syenites, and others. It is often unevenly distributed in the rock, and you observe rich pods with a high volume Corundum in an otherwise nearly barren rock.
Ruby and Sapphire are some of the most cherished and valued of all gems. They are both colour varieties of the mineral Corundum, but there is no clear definition of them. Corundum can take almost any colour, and most of natural Corundum is either grey, brown or black, and unsuited for gems.
More modern terminology requires Sapphire to be 'corn flower blue' Corundum, Ruby to be 'red like fresh pigeon blood', and all other colours (yellow, pink, peach, ..) are 'fancy Sapphires'. It sounds very nice, but is not very practical. Imagine going to the jeweler to pick a ruby. Not only do you have to carry a live pigeon with you, you also have to chop its head off in the shop and compare the stones to the colour of the blood. Generally, jewelers don't like that! For practical purposes, it is better to assume rubies are dark, clean red - not purplish, not brownish, not pink - and sapphires are clean, dark blue. Everything else is a 'fancy sapphire'.
Corundum can be found in several different types of 'silica deficient' rock, that is rocks without Quartz. These include syenites with much feldspar and amphiboles, limestones, as well as a few more exotic types. Corundum is very hard, and it is often mined from so-called secondary deposits like river gravels, where the Corundum is preserved even if the rest of the rock has decomposed. As a matter of fact, only very little Corundum is mined from primary rocks.
Most of the great classic deposits of Ruby are in Asia. The most important are Myanmar (Burma), Afghanistan. Both produce beautiful rubies from a white limestone and nearby river gravels. Ruby also comes from India and Sri Lanka (Ceylon), as well as a few places in Africa. A very attractive material, bright red Ruby in deep green Zoisite comes from Tanzania. This is rarely of gem quality, but a very attractive specimen material.
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.
is one of the ancient capitals of Sri Lanka, famous for its well-preserved ruins of ancient Lankan civilization.The city, now a UNESCO World Heritage Site, lies 205 km north of the current capital Colombo in Sri Lanka's North Central Province, on the banks of the historic Malvathu Oya.
Founded in the 4th century BC, it was the capital of the Anuradhapura Kingdom until the beginning of the 11th century AD. During this period it remained one of the most stable and durable centers of political power and urban life in South Asia. The ancient city, considered sacred to the Buddhist world, is today surrounded by monasteries covering an area of over sixteen square miles (40 km²). Anuradhapura is also significant in Hindu legend as the fabled capital of the Asura King Ravana in the Ramayana.
Further excavations in Anuradhapura have uncovered information about the existence of a protohistoric habitation of humans in the citadel. The protohistoric Iron Age which spans from 900 to 600 BC, marked the appearance of iron technology, pottery, the horse, domestic cattle and paddy cultivation. In the time period 700 to 600 BC the settlement in Anuradhapura had grown over an area of at least 50 ha. The city was strategically situated of major ports northwest and northeast, it was surrounded by irrigable and fertile land. The city was also buried deep in the jungle providing natural defence from invaders.
Lower Early Historic period
The Lower Early Historic period, spanning from 500 to 250 BC, is studied on the lines of the chronicles. During this time King Pandukabhaya formally planned the city, with gates, quarters for traders etc. The city at the time would have covered an area of 1 square kilometre which makes it one of the largest in the continent at the time.
The city grows
The city's popularity grew both as a ritual centre and as the administrative centre, a large population was attracted to the city for permanent settlement. Thus the living facilities were improved to accommodate the expanding population. King Vasabha constructed many ponds which were fed by a network of subterranean channels which were constructed to supply water to the city. Tissa and Abhayavapi tanks were built, the Nuwara weva was built and the Malwatu Oya was dammed to build the Nachchaduwa wewa which was 4408 acres (17.84 km²) in size.
Parks were also provided in the city. The Ranmasu Uyana below the bund of Tissavapi or Tisa weva was one such, but it was strictly reserved for the members of the royal family. Health care and education were two other aspects to which the authorities paid attention. There were several hospitals in the city. In the forth century King Upatissa II provided quarters and homes for the crippled and the blind. King Buddhadasa (337-365 AD), himself a physician of great repute, appointed a physician to be in charge of every ten villages. For the maintenance of these physicians, one tenth of the income from the fields was set apart. He also set up refuges for the sick in every village. Physicians were also appointed to look after the animals. Kassapa V (914-923 AD) founded a hospital close to the southern gate of Anuradhapura. General Sena in the tenth century is believed to have built a hospital close to the ceremonial street (Managala Veediya). The history of medical care began early, for in the fourth century BC King Pandukhabaya, in the course of sanitizing the town constructed a hospital. A large workforce was entrusted with the task of keeping the city clean.
Large lakes were also constructed by the city's rulers to irrigate paddy lands and also to supply water to the city. Nuwara wewa and Tissa wewa are among the best known lakes in the city.
The great city
Anuradhapura attained its highest magnificence about the commencement of the Christian era. In its prime it ranked beside Nineveh and Babylon in its colossal proportions—its four walls, each 16 miles (26 km) long, enclosing an area of 256 square miles (663 km²) —in the number of its inhabitants, and the splendour of its shrines and public edifices. The city also had some of the most complex irrigation systems of the ancient world, situated in the dry zone of the country the administration built many tanks to irrigate the land. Most of these tanks still survive. To date, it is believed that some of these tanks are the oldest surviving reservoirs in the world today.
The ruins consist of three classes of buildings, dagobas, monastic buildings, and pokunas. The dagobas are bell-shaped masses of masonry, varying from a few feet to over 1100 ft (340 m) in circumference. Some of them contain enough masonry to build a town for twenty-five thousand inhabitants. Remains of the monastic buildings are to be found in every direction in the shape of raised stone platforms, foundations and stone pillars. The most famous is the Brazen Palace erected by King Dutugamunu about 164 BC. The pokunas are bathing-tanks or tanks for the supply of drinking water, which are scattered everywhere through the jungle. The city also contains a sacred Bo-Tree, which is said to date back to the year 245 BC. The railway was extended from Kurunegala to Anuradhapura in 1905.
Please, send me answers for this questions via my profile on geocaching.com and photos attach to your log.
Your task is:
1/ Take a photo of you with The Ruwanveli Saya Stupa
2/ What type of rock it is that the platform of the Ruvanwelisaya stupa. Be specific.
3/ Write me what type of rock it is. (Igneous, Metamorphic, or Sedimentary)?
4/ What is crystalic system of sapphire?
5/ What is chemical formula of sapphire?