INDUSTRY Once prized for their mystical powers, diamonds from the Golconda mines of India remain among the most coveted of gems. GolcondTahMe ystiqBY DuR. E RIC e EREL olconda diamonds were mined in the the country where diamond mines were originally discov - ancient kingdom of Golconda in south ered.As early as 800 B.C., Indian diamonds were collected central India — today the state of Hyderabad in secondary deposits.At the end of the thirteenth century, — beginning more than 2,000 years ago. For Marco Polo, the renownedVenetian traveler, visited the centuries, diamonds from these mines have been kingdom of Warangal and described the process of collect - prized for their incredible transparency,whiteness ing diamonds that took place after heavy rains fell, in the and purity.The renown of the Golconda mines also owes beds of the torrents. Later, mines were also dug underground much to the fact that a number of the world’s most in ancient alluvial deposits, and diamonds were historically significant diamonds have come collected in tunnels and open pits. The leg - from these mines. These stones include endary French diamond merchant Jean the Koh-I-Noor, the Regent, the Great BaptisteTavernier, who visited numer - Mogul and theTavernier Blue, from ous Indian diamond mines between which the Hope Diamond is the years 1630 and 1668, reported believed to have been cut. that as many as 60,000 persons Today, true Golconda diamonds were working in the mines at any are extremely rare and exist one time. mainly in museums or collections of renowned persons like Indian THE MAGIC OF rulers, European kings or rich con - GOLCONDA noisseurs, who can trace them back Mysticism and other magical to the eighteenth century or earlier. powers were always associated with Occasionally, such stones may come diamonds in the culture of India. up for sale at auction by Christie’s or Diamonds were seen as talismans and Sotheby’s but that is a special occasion. were believed to contain powers derived from Over time, the term Golconda diamonds has the gods. For the transfer of beneficial influences evolved to describe diamonds with the same high level of — such as happiness, wealth, prosperity or children — to transparency, clarity and whiteness as the diamonds actu - occur, the persons possessing diamonds were required to ally mined in Golconda. Since the 1980s, the Gübelin Gem meet certain qualifications of rank and status. Only kings Lab has issued a Golconda Appendix as an addition to its and priests, for example, were allowed to possess the pure, grading report for exceptional diamonds that show a com - colorless Golconda diamonds. bination of rare properties, such as an antique cutting style Since the earliest times, the quality criteria for diamonds and superior color and clarity.To earn this appendix, these were mainly correlated to their shape, color and clarity. An stones also must qualify as type IIa diamonds, signifying that they are free from nitrogen and therefore chemically pure. This page: 5-carat-plus, D color, type IIa diamond. To understand the significance of the Golconda descrip - Opposite page: 20-carat, D color, internally flawless (IF) type IIa tive, it is necessary to go back thousands of years to India, diamond, courtesy Horovitz & Totah. Photos by Eric Erel. 170 Rapaport Diamond Report January 2009 ideal diamond crystal had to possess a perfect octahedral beginning in the eighteenth century, this situation changed form, to be free of any blemishes and to be perfectly white. dramatically with the discovery of diamonds in Brazil in Such a diamond crystal, like the prism, has the power to cre - about 1730 and in Africa, in about 1870.Today, diamonds ate the“magic” rainbow by dividing the sunlight into all the are extracted in many countries and, due to the absence of spectral colors.This important optical property was associ - criteria for geographic origin, it is impossible to determine ated with talismanic forces. Mystical interpretations say that where specific individual diamonds were mined. only a rough diamond possesses beneficial virtues. That explains why, when diamonds were set in jewelry before the IDENTIFICATION fourteenth century, they were usually in their natural shape. The typical Golconda shapes are table cut and the suc - ceeding, more faceted cuts in use until the eighteenth ORIGINS OF CUT century, including cushion, oval, old pear and marquise The earliest evidence of cutting — polishing and cleav - shapes with rounded ends, as well as other shapes with irreg - ing — dates to the fourteenth century and appeared at the ular outlines.These antique cuts usually display, among other same time in India and in Europe. The point cut, which criteria, a high crown, large culet, numerous and irregular resembles a four-sided bipyramid, is believed to be the first extra facets and both naturals and indented naturals that diamond cut. This cut, which remained popular until the remain from the original surface of the rough. Renaissance period, improved the shape of natural According to modern grading systems, these stones would octahedral crystals into a more perfect form. be characterized by a low polish and symmetry grade, and The next to appear was the table cut, obtained by the often with a low clarity grade as well. Due to the cutting truncation of one point with a polished and flat surface techniques between the fourteenth and eighteenth cen - called the table. Sometimes a lower point could also be cut turies, when it was impossible to get a perfectly polished out in order to add a small culet.This cutting style domi - and symmetric diamond, the presence of flaws near the sur - nated from the end of the fifteenth century until the face had more to do with the quality of the finish than with seventeenth century. During that period, many point cut the clarity of the diamond. For this reason, a Golconda stones were recut into table cuts. Appendix does not necessarily indicate a flawless The third cutting style, introduced in the or internally flawless (IF) stone. Diamonds sixteenth century, was the rose cut.This with lower clarity grades, which can cut, characterized by a flat bottom and become IF after a minor recutting, are a domed front with triangular facets, also eligible for this appendix. was immensely popular until the In terms of color, only colorless nineteenth century. Other cutting diamonds with a D color grade styles that appeared between the are eligible for the Golconda fifteenth and the sixteenth cen - Appendix, as well as certain fancy turies simply added facets to table colors exhibited by one of the his - cut stones. torical Golconda diamonds, such At the beginning of the seven - as the blue Hope or the pink teenth century, the Mazarin cut was Grand Condé. developed, named after Cardinal Jules The last criteria for the Golconda Mazarin of France, who lived from 1602 Appendix are related to the size and to 1661.This cushion-shaped diamond was type of the diamond. The appendix is one of the earliest faceted cuts and contained restricted to type II diamonds only because 34 facets. Following the Mazarin cut, the brilliant cut, most of the large, historical Golconda diamonds are known as the old mine cut today, was introduced. It type IIa stones and because type II diamonds are very rare. contained 58 facets, the same as the modern brilliant. More For the Gübelin Gem Lab, the Golconda Appendix is conical shapes with rounded outlines were also cut and called designed to reflect the high quality and rarity of the large brilliant cut.The brilliant cut was popular from the middle and historical diamonds that originated in India’s Golconda of the seventeenth through the eighteenth century and many mines.This appendix is delivered very rarely and only for previously cut diamonds were recut in this style in order to exceptional diamonds, whatever their geographical origin, modernize them. By the nineteenth century, the shapes in accordance with the quality criteria seen in India thou - became more rounded and, at the beginning of the twentieth sands of years ago and the properties known to be typical century, the modern round brilliant appeared. of the famous Golconda diamonds. From antiquity until the eighteenth century, diamonds Dr. Erel is a gemologist with the Gübelin Gem Lab were very rare and most of them originated in India. However, in Lucerne, Switzerland. Rapaport Diamond Report January 2009 171.