Universally esteemed as the finest diamonds, 'Golconda' is a name used within the jewellery world to denote diamonds which possess superb luminousness and transparency. Besides indicating a superior quality, the term also indicates that the diamond is an old stone, mined in the ancient diamond fields of Eastern India.
The characteristic which sets Golconda diamonds apart from all other diamonds is a subtle luminous quality. It is an attribute which causes otherwise articulate connoisseurs to be at a loss for words when they attempt to describe it.... "I could talk for hours about Golconda stones. But to really know what I am trying to tell you, you must hold one in your hand. Only then will you understand".
Golconda diamonds have a degree of transparency rarely seen in stones from other countries, such as South Africa, Russia, Canada or Australia. It is variously called, soft, limpid, watery or pure. It is not to be confused with clarity or freedom from flaws - it is rather a quality in which light appears to pass through the stone as if it were totally unimpeded, almost as if the light were passing through a vacuum. In addition, the surface lustre appears to have a light softness, more gentle and yet luminious and striking.
For the connoisseurs, the Golconda diamonds which retain their original cuts are most appreciated. Since the stones may have been mined hundreds of years ago, many exhibit the slightly less than precise cutting styles common prior to this century. This older cut tends to emphasize the limpid transparency which makes Golconda diamonds so special. Today, it is extremely rare for a diamond to be considered worthy of the "Golconda" attribution. Even though there are modern stones which exhibit similar qualities of luminousness and transparency, they can only be certified as "Type IIa" diamonds.
It is widely accepted that all diamonds which display this special luminousness are of Indian origin. Although little is recorded of the very early days of diamond mining in India, it is believed that it began about 400BC. For about 2000 years (with the exception of a small and protected source in Borneo), this was the only source of the precious gems until about 1725 when diamonds were discovered in Brazil, coincidentally at the same time as the majority of India diamond mines were depleted. Since 1829 the alluvial deposits have been worked in the Ural mountains of Russia and in 1866 the large diamond finds of South Africa were discovered. Diamonds in Australia were first recorded in 1851 but it was not until the 1979 that Argyle pipe was discovered and most recently Canada has become a forerunner in diamond mining. However, compared to the age of the Indian mines, all other diamond producing areas are comparatively recent discoveries.
The Indian diamond fields are found scattered throughout a broad belt of ancient rocks extending nearly one thousand miles in the north-south direction along the eastern half of the country. The vast majority of the diamonds found were from alluvial deposits - a secondary deposit formed by the breakdown of older rocks by the forces of nature and set down in river beds. Within the diamond belt, diamonds were found in five distinct districts, each separated by high terrain. Each district had its own name, the most famous being the Golconda district centred around the area capital, trading centre and ancient fort of Golconda. Comprising Kistna and Godaviri valleys, mining activities reached its climax in the mid 1600s, according to the writings of the celebrated gem merchant and traveller Jean Baptiste Tavernier, and it is the Golconda district which is believed to have yielded the great historical diamonds of India, including the Koh-I-Noor, now part of the Crown Jewels of England, and the infamous deep blue Hope diamond, donated by Harry Winston to the Smithsonian Institute in Washington.
Today, diamond production is a fraction of what it was during the 1600s and is overshadowed by mining in Africa, Australia, Russia and Canada. However, it is still the Golconda diamonds which reign supreme among gem connoisseurs around the world in terms of quality, mystery and romance.