Flying Into the Heart of the Colombian Emerald-Mining Region

NEWS 27/01/2016 Flying Into The Heart Of The Colombian Emerald-Mining Region Bogotá, Colombia played host to the First World Emerald Symposium from October 13 to 15, bringing together various stakeholders of the Colombian and international emerald industry. Vital to the event were the various presentations made by Colombian (FEDESMERALDAS) and other trade organizations, private individuals, laboratories, scientists from universities and large mining companies, such as Muzo International and Gemfields. Topics covered a broad range of information creating an atmosphere for the exchange of data between attendees. The presentations featured an introduction to the geology of emerald formation, mineralogy and the engineering side of mining operations, focusing on various emerald mines around the world. RS Gemresearch Swisslab AG was invited to take part in the Symposium in order to address the topic of color grading of emeralds. Following the presentation by Dr. Adolf Peretti, he was part of an expert panel of debaters who discussed topics such as the marketing of emeralds and various laboratory GGissues, including disclosure of treatments, color grading and origin determination. And he also organized an expedition into the remote areas where Colombia’s main emerald mines are located. FEDESMERALDAS, the Colombian Emerald Federation, the country’s national organization which represents emerald producers, merchants, dealers and exporters, organized trips to various key mining sites in Colombia’s Eastern Andes ‘Cordillera Oriental’. Large mining companies openly welcomed a group of people to acquire first-hand insight from miners and experts in the field. This experience provided a unique opportunity for the group to cobine theoretical knowledge with practical field experience. GRS organized its own small expedition in tandem with the larger group’s expedition at the three different mining areas of Chivor, Cunas (La Pita area) and Muzo. We had to hand over our equipment for our filming and sampling activities, since we did not want to disrupt the organizers of the official field trip. The expert GRS group included Adolf Peretti and Willy Bieri, and was accompanied by Jean Claude Michelou, former ICA Vice President, Colombian emerald expert and advisor to the UN, as well as former ICA President Wilson Yuen from Hong Kong. The expedition was conducted via private transportation as well as helicopters that provided efficient use of time for our visits to the mines. The GRS-sponsored expedition had the following objectives: Visit the mines, meet the miners and interview them about their mining experiences Enter the mines to collect rocks and emerald specimens of known origin Survey the mines with a drone to gather aerial reconnaissance Obtain film and photographic footage of the interior and exterior of the mines This field trip provided the foundation for future GRS seminars with a focus on Colombian emerald mines. In this article, we cover our expedition and share some of our experiences via a selection of images and video clips. Video clips of interviews with the miners and geologists are also included (see box). We also visited the TMC (Texas Mining Company) Muzo mine during the trip, but no filming was allowed inside that mine. So, instead, GRS offers photographic images and clips of these mines and inside the tunnels from previous expeditions to the Muzo mines from our archives (Figs. 22-24). As our recent inspection revealed, the documentation is still valid and accurately represents some aspects of current mining activity and their geology. Fig. 2 Fig. 3 Fig. 1 Fig. 6 Fig. 4 Fig. 5 Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 11 Fig. 12 Expedition to Chivor The journey to Chivor from Bogota takes about 4-and- a-half hours using a 4-wheel-drive vehicle. The emerald mining area we visited is situated in the Western Cordillera of the Andes (4° 51’ 10.08” N, 73° 23’ 6.72” W). On arrival, we were granted access to a private mine operated by SOESCOL Ltda and managed by Ubaldo Montenegro. The miner drove us in his specially designed 4×4-wheel vehicle to ‘San Gregorio’ ,one of his local mining titles. A few mining shafts were visible and we chose one for a closer inspection. We had to walk 2.7 km inside the mountain for a total of 5.4km there and back. This was a hard two-hour walk under conditions of extreme heat and high humidity. We were equipped with helmets, lamps and special boots plus a sufficient water supply to withstand the tunnel trek that took us deep into the mountain with temperatures reaching far above 40°C. It was necessary to pass a heavy steel door that keeps uninvited guests out of the mine. Inside the mine we encountered an emerald-bearing vein that had been mined only a couple of hours prior to our arrival. This was where we also met with miners who worked this part of the shaft. It was a rare opportunity to document the geology of the veins and acquire emerald material that had just been mined at this exact spot. One of the authors (Adolf Peretti) hammered Colombian emeralds directly from the rock (Fig. 3). Such samples are vital as they can be used for comparison against the results that are published in trade literature. They were carefully labeled and packaged for later chemical and sulfur isotope analyses. It was interesting to see the large and beautiful pyrite formations that accompanied the emeralds in the host rock (Fig. 5). The mine owner allowed us to operate a public licensed remote-controlled drone in order to properly survey the landscape. The drone allowed us to document the large- scale geological formations of the mine with a true bird’s-eye perspective (Fig. 6). We were able to acquire commercially relevant emerald rough of various shades of green from miners from a different tunnel (Fig. 11). These samples were later polished in our laboratory for calibration of different color varieties from the Chivor mining area. Outside the mine, we came across some hard working Colombian miners (Fig. 9). Their faces were covered with black graphite soot from underground exposure and the rock particles of its surrounding host rock to the Colombian emeralds. The green rough emeralds were in stark contrast to the miner’s hands. Those miners’ hands symbolize the extremely hard conditions involved in this kind of mining activity. Jean Claude Michelou assisted us with translation during the research sample acquisition for the laboratory using his expert negotiating skills and knowledge of the local customs (Fig. 4). The mines appeared to be involved in relatively small-scale mining. It appears that there were many liberties taken with regard to security and safety as we realized when comparing it with other very large mines in the east of the Andes. Our car was equipped with a GPS, which allowed us to return to Bogota the same day through the total darkness of the remote tropical areas. Expedition to Cunas (La Pita Area) and Muzo The following day we flew from Bogota by chartered helicopter but were only allowed to fly into the Cunas mine (5° 35’ 49.20” N, 74° 5’ 12.94” W). The TMC Muzo mine did not grant us landing permission. The Cunas mine, however, is very close to the Muzo mines. Both mining areas are situated among beautiful mountain landscapes along the River Mineros; approximately 40 minutes flying time from Northern Bogota airstrip Guaymaral. The flight path follows some fantastic scenery. It provided us with an impressive view into a natural paradise nestled in a classical area that had been riddled with conflict from different origins in the past (Fig. 25). However, the region is now “pacified” and this area was exceptionally made accessible to us. Previously, only very important emerald dealers were granted access to these mining areas. This was not possible without the heavy protection that the groups relied upon for security measures. The Cunas mine is a medium-sized enterprise of commercial importance professionally organized by the Esmeraldas Santa Rosa company. The helicopter-landing pad is idyllically situated atop one of the steepest mountains emerging from the emerald-bearing river (Fig. 13). We carried out a few extra flights around some very dramatic mountain peaks in the area (Fig. 25). On arrival, we were permitted to operate our drone over the Cunas mining area. The drone was followed by a few vultures, which constantly circled the mining camp. At lunchtime, we took the opportunity to interview the mine operation manager Alejandro Lemaitre (see box). The miners, we noticed, were being served food from a very clean, hygienic kitchen. We then encountered some miners performing gymnastic exercises in preparation for the arduous work that followed during their next shift (Fig. 16). The descent from the Cunas mining camp from the top of the mountain to the river was steep, and heavily armed guards were observed on the way (Fig. 15). The mining operation is constantly confronted with air quality difficulties inside the tunnels, which have to be continuously monitored (Fig. 19). The mine tunnels are re-enforced with wooden supports. Small steel carts bring out the black crushed rock from the mines. Emerald-bearing veins are sealed in special bags right after they are discovered and are labeled with detailed information and then secured by a supervisor. It was possible to take some rock samples, but they did not contain emeralds. Of our two film cameras, one stopped working when the temperature and humidity reached extreme highs. Large amounts of water were constantly being pumped out of the mines. The vein formation was different here. Some geological sketches could be drawn to record the details of the direction of shear zones, calcite veins and pyrite formations.

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