THE COSCUEZ MINE: A MAJOR SOURCE OF COLOMBIAN EMERALDS By Ron Ringsrud The Muzo emerald district, in Boyacd, henever fine emeralds are discussed in the gem Colombia, contains several mines. w trade, the term Muzo is invariably used to describe Although the Muzo mine is undoubtedly the best. Yet Colombia's Muzo district actually the best known, the Coscuezmineis rapidly encompasses several mines, of which two are currently gaining significance as a major source of major producers: Muzo and Coscuez. Many stones prop- fine emeralds. Yet few in the trade outside erly referred to as "Mum emeralds" actually come from of Colombia are aware of the importance of Coscuez (figure I), which lies only 10 km from the Muzo Coscuez orJznow about the emeralds mined 2). there. The '~oscuezmine is literally mine (figure Although smaller than Muzo, the Coscuez hundreds of years old, and its history is mine has for more than 300 years produced some of the closely tied to that of Muzo, Located only best emeralds from the Muzo region, at times in quantities about 10 lzm apart, the two areas also share that have even surpassed the Muzo mine. many geologic features and both are Five years ago, Gems o) Gemology published an article currently exploited using open-cut mining outlining the history, geology, and production of Colom- methods. The Cosczzez emeralds are similar bia's two major emerald-mining regions: Muzo and Chivor to Muzo stones in their physical properties, (Keller, 198 1). Soon after that article appeared, however, but they occurin a somewhat broaderrange production from the Chivor region began to fall, while that of hue and saturation. Prospects for even from the Coscuez mine accelerated rapidly. During this greaterproduction at Coscuez in the future same period, the Muzo mine continued to supply good are good. quantities of emeralds. Today, most of the emeralds mined in Colombia come from the Muzo district, and the Cos- cuez mine has grown to become the second largest pro- ducer of emeralds in Colombia. Yet in spite of its prominence, little has been written ABOUT THE AUTHOR specifically on Coscuez or the Coscuez emeralds in the Mr. Ringsrud is a major partner in Constellation jewelry and gemology literature, and few in the trade out- Gems, Inc., an import firm specializing in Colombian emeralds, which is headquartered in side of Colombia are aware of its importance as a major Los Angeles, California. source of fine emeralds. In March 1984, the author traveled Acknowledgments: The author would like to thank to Coscuez in the company of local dealers; two years later, the following people for their assistance in in May 1986, he revisited the mine as a guest of Colombian researching and completing this article: Samuel, Mines Co., a major stockholder of ESMERACOL, the pres- Amnon, and Albert Gad; Jack and James Rotlewicz; Jorge Rozo; Eileen Weatherby; Gabriel Acufia; Dr. ent leaseholder of the Coscuez mine. Based on information Alfonso Soto: Raul Escobar; Humberto Rodriguez; gathered during these visits as well as from other sources, Guillermo Cano; Dr. Peter Keller; Dr. James Shigley; this article reviews the fascinating history of mining at Benny Bazalel: Alberto Florez; and Cornelio Torres. Unless otherwise noted, allof the locality photos are Coscuez, describes thegeology of the area and the nature of by the author. mining operations, and examines the gemology of the Cos- 0 7986 Gemological Institute of America cuez emeralds. Emeralds from Coscuez GEMS & GEMOLOGY Summer 1986 67 HISTORY jungle traps, camouflaged pits, and numerous for- Much interesting history about the Spanish dis- tifications. covery and conquest of the emerald regions of Col- The Muzos inherited from their ancestors the ombia was published in 1948 by the Bank of the ancient legends surrounding the Fura-Tena, a co- Republic after it took over the administration of lossal pair of granite peaks (the tallest is 625 m emerald mining from the government. The author above the Minero River), approximately 40 km was G. Otero Mufioz, head of the Colombian Insti- from the Coscuez mine. As one approaches from tute of History. Unlike many other publications, the east, the Fura-Tena looms up majestically as a Esmeraldas de Colombia provided considerable sentinel to all who enter the emerald region. One information specifically on Coscuez. Much of Muzo legend states that Fura is the prince and what follows is from this source. Tena is the princess, both born to the god of the In their conquest of South America, beginning mountains. The god gave them wealth in the form in the 16th century, the Spaniards encountered of rich veins of emeralds, one of which was sacred Colombian emeralds among the local Indians as and not to be touched. A devil named Zarv con- far north as Mexico and as far south as Peru and vinced the princess to take the forbidden stones. northern Chile (Sinkankas, 1981). Judging from As she and the prince attempted to remove the the emeralds found in these ancient Indian sites, cursed emeralds, the god turned them into the two archaeologists believe that pre-Colombian tribes granite peaks, and their tears of remorse became began to systematically mine and trade emeralds the Minero River. as early as 1000 A.D. (Sinkankas, 1981). In the In 1538, Spanish Captain Luis Lanchero region near present-day Bogota, Spaniards led by launched the first campaign against the Muzo Gonzalo Jimenez de Quesada easily conquered the Indians (Piedrahita, 1881).Although Lanchero was Chibcha and Fusagasugae Indians. From the Chib- forced to retreat after much fighting, accounts of chas, the Spaniards learned of an emerald mine at a the campaign show that while butchering local place called Somondonco, which they located in wild turkeys for food, he and his soldiers found 1537 and later renamed Chivor (Wokittel, 1960). small emerald crystals in the craws. This was more The Chibchas also told them of another rich em- than enough incentive to convince the colonial erald area to the northwest. But to penetrate this governors to continue attempts to conquer that region, the Spaniards would first have to subdue a region. More campaigns were launched against the far more formidable tribe: the Muzos. The Muzos Muzos in 1545,1550, and 1551, but these too were were known as the most warlike, ferocious, and ultimately unsuccessful. valiant Indians in the region, and further were re- In 1558, however, Lanchero reentered Muzo ported to be cannibals. They were famous not only territory with a force consisting of Spanish soldiers for their poison arrows, but also for their hidden and members of local tribes that were also at war 68 Emeralds from Coscuez GEMS & GEMOLOGY Summer 1986 7COLOMBIA, Figure 2. The Muzo and Chivor emerald-mining districts in Boyacd, Coloinbiu, Note the proximity of the Coscuez and Muzo mines to each other. Mines %' Cities / *Rivers 0 20 km with the Muzos. Up until this confrontation, the bringing the land of the Muzos under Spanish steel swords, armor, and firearms that had been control. adequate to conquer local Indian tribes throughout Following their success, in 1559 Lanchero's much of the continent had not been enough to men created a settlement close to where the subdue the Muzos. Their defeat was ultimately Indians' emerald mines were supposed to be and brought about by Lanchero1s timely use of a new called it Santisima Trinidad de 10s Muzos. Captain weapon: ferocious European hunting dogs. When Lanchero and his men soon located the mines and the dogs were turned loose in mid-battle, they cre- began to work them in the name of the Spanish ated havoc and confusion in the ranks of the Crown. Coscuez, named after an Indian princess, Indians (figure 3). In two costly and decisive bat- had been worked by the Indians for centuries prior tles, Lanchero and his forces finally succeeded in to the conquest and was undoubtedly one of the Emeralds from Coscuez first located by the Spaniards. Ironically, a chest changed the operation at Muzo from tunneling to wound that Lanchero had received more than two open-cut mining, using a form of benching, that is, decades earlier in his first battle with the Muzos cutting the slopes horizontally in a step-like fash- had never healed, and in 1562 it turned gangrenous ion and washing away the resulting debris with and killed him. Yet the value of the legacy he left water. Because water was not as readily available, was evident in the eventual establishment of a Coscuez was worked less extensively at this time, royal counting house, a royal treasury, and numer- and mainly by tunneling. Paris is remembered ous cathedrals in the town of Muzo. The cost to the today primarily for his part in the discovery at Muzo Indians, however, was dear: Enslavement to Muzo of the mineral parisite, a rare fluorocarbo- work the mines and exposure to new diseases in- nate of cerium that was named in his honor. After troduced by the Spaniards killed thousands. Even- Paris, a number of foreign and Colombian lessees tually the loss of slave labor led to a steady decline continued to work the deposits with varying de- in emerald production, and the seat of local gov- grees of success. Little has been recorded about ernment was moved from Muzo to Tunja. activity at Coscuez during the latter half of the Spanish records indicate that in July of 1646 19th century except that it was repeatedly worked, there appeared in the city of Muzo a Captain abandoned, and reopened (Pogue, 1916, Op- Francisco de Ovalle, carrying a royal seal that penheim, 1948). named him Lord of Mines and overseer of all that he discovered in the Coscuez heights "as long as RECENT HISTORY AND the rocks there show the green of the emerald." PRODUCTION This situation caused some official confusion at The Muzo mine was responsible for most of the first, because the mine was already known and emeralds produced in the district from 1925 until being worked by others.