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A look at the culture, mines and landscapes of this relatively new source
of copper-bearing tourmaline
Story and photos by Brendan M. Laurs
Editor's note: Brendan Laurs, editor of Gems & Gemology (G&G), and Hanco Zwaan, of the Netherlands Gemmological Laboratory/National Museum of Natural History "Naturalis," Leiden, visited Mozambique last year to get information on the location, geology and mining of an important deposit of ParaÃba-type tourmaline.
They were guided by Salifou Konate and Chirindza Henrique from Mozambique Gems, and stayed in their mining camp for five days. The company, owned by Moses Konate and partners Saint Clair Fonseca Jr., Daniel Trinchillo, Burkhard Pohl, and Marcus Budil, filed the first mining claim in the area for the Paraíba-type tourmaline, and has been preparing for a major mechanized operation.
The future production of copper-bearing tourmaline from Mozambique is expected to increase as mechanized mining activities commence in the coming months. An article with more information on this tourmaline is being prepared for submission to G&G.
Copper-bearing tourmaline from Mozambique is found as waterworn pebbles in a variety of colors. These relatively large samples are reportedly unheated.
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Tourmaline, in a variety of vivid colors, was first recovered from a new area of the Alto Ligonha pegmatite district in northeastern Mozambique in 2001. In 2003, Moses Konate discovered that it contained traces of copper, and some stones turned bright blue to blue-green when heated to moderate temperatures. Mozambique then joined Brazil and Nigeria as the world's only sources of this beautiful and valuable "Paraíba" tourmaline.
A visit to this part of Mozambique is as colorful as the tourmaline itself. Shortly after its discovery, a gem rush ensued and the nearby village of Mavuco turned into a booming frontier town, with perhaps 7,000 people living and working in the area. The town is located more than an hour's drive from the nearest paved road, and has no electricity or running water.
Artisanal miners came from near and far. Entrepreneurs set up shop in thatched storefronts. Gem traders came from West Africa and employed a network of "runners" to bring the stones from the miners. So far, most of the tourmaline has been produced from an area of about 3 square kilometers by small groups of informal diggers using hand tools to reach the gem-bearing horizon.
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Smiles and bright colors commonly greet visitors to Mozambique.
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The stones are found as waterworn pebbles in an alluvial layer buried beneath up to 5 meters of laterite soil. Using picks and shovels, the miners dig small pits that are abandoned after searching through the narrow layer containing the gems. The extent of the tourmaline-bearing horizon has not yet been determined, although the miners reported encountering only black tourmaline on some edges of the mined area, leading them to search elsewhere.
On their 300 hectare mining concession, Mozambique Gems has performed systematic mapping and test pitting, and has completed a comprehensive environmental impact report. The company is building a washing plant capable of processing 150-200 tons of material per day. It will begin mining and simultaneous reclamation of the pits when the plant is completed in early to mid-2008. In addition, the owners of the mineral rights in the surrounding area have consolidated their claims and are making preparations for mechanized mining.
In the past, most of the tourmaline was routed through the West African buyers to the regional capital of Nampula (about 90 kilometers north of Mavuco), where it was purchased by other West African dealers and rough stone buyers from Brazil, Germany and Thailand. In the future, the stones produced by Mozambique Gems will be channeled directly to large cutting wholesalers and television shopping networks.
We purchased some small tourmaline samples in Nampula from a parcel of rough material that was reportedly mined from the Mavuco area. The waterworn pebbles – all reportedly unheated – showed a range of colors and sizes. We obtained chemical analyses of the samples and were surprised to learn that three of the 20 pebbles were not tourmaline. Instead, they consisted of amethyst, light yellowish-green fluorite and light bluish-green manufactured glass. In addition, a light green pebble that was obtained directly from one of the miners at the pits was identified as fluorite.
Identifying such imitations in the field can be challenging when dealing with multicolored parcels of waterworn rough – buyer beware!
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A local guide led the way on a trek up Mt. Muli, a granitic monolith located a few kilometers south of the mining area. The typically flat landscape in this part of Mozambique is punctuated by these hills that rise steeply for several hundred meters above the surrounding plains.
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Most of the production of copper-bearing tourmaline from Mozambique has come from artisanal miners working in small pits such as these. They dig through the overburden until they reach the tourmaline-bearing horizon, and then go through the material with their picks to look for gems. Although many stones are probably overlooked in the process, water for washing the soil in this part of the mining area is scarce or unavailable during most of the year. Dry screening is not feasible since the tourmaline-bearing layer
is cemented by clay.
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A local dealer holds a gemmy pebble of tourmaline that has just been unearthed. Such pieces are sold by the gram, either one at a time or in small parcels, and many buyers have noticed increasing prices in recent months. We were told that one reason for the rising prices is that the local dealers have seen high dollar amounts asked for faceted Mozambique tourmalines on various Internet sites.
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One of the companies involved with mining the Paraíba-type tourmaline funded the development of a new school in Mavuco. A medical clinic is also being constructed in the town.
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Bicycles are the preferred form of transportation for local miners – and for their tools. Jugs of water, bundles of firewood, bags of charcoal and anything else that can be strapped to them, are commonly carried on bicycles.
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Ranging from 6.73 to 16.50 carats, these faceted copper-bearing tourmalines show some of the vivid colors produced from Mozambique. The stones are reportedly unheated except for the one on the far left. Courtesy of Barker & Co., Scottsdale, Arizona, and Pala International,Fallbrook, California; photo by Robert Weldon.
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Local shopkeepers offer picks, shovels and other durable goods in the town of Mavuco. Jeans, bicycle parts, music CDs, batteries, groceries and cooking utensils are also commonly seen for sale.
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This friendly vendor offers live poultry to passersby en route to the mining area. Sundays are the most popular market day in Mozambique for those living in cities or more remote areas of the countryside.
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A local digger returning from the mines is passed by “runners” on a motorcycle. The runners bring stones from the miners to the buyers in town. Their share of the profits has enabled them to buy the motorcycle, a definite status symbol in this region.
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Material from the test pits is brought to a local stream so the water can be used for washing and screening. The stones on each of the screens are then hand-picked for tourmaline.
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A backhoe, on Mozambique Gems’ concession, is used to explore for the tourmaline-bearing horizon in a series of test pits. The author is getting a free ride to the bottom of the 4-meter-deep pit where the gem-bearing layer is exposed. Photo by J. C. (Hanco) Zwaan.
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The main street in Mavuco was bustling with activity during our visit. We passed stone buyers, shops, restaurants, bars and even a barber shop, as we walked through town.
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Check for Scorpions First!
Visiting remote areas for fieldwork commonly involves doing without certain conveniences such as running water or electricity. The field camp where I stayed in Mavuco was quite comfortable, however, with sturdy buildings made from cement blocks and corrugated metal roofing. In the evenings, a generator provided electricity for light bulbs, a refrigerator and a TV with satellite access to stations around the world.
After dinner each night, when many of the mine personnel tuned into Brazilian soap operas, I would take a bath at the washroom facilities located in a separate building. A plastic bucket filled with water from the local river sat next to the bath tub; sometimes it was heated first in the kitchen using a charcoal stove, sometimes not. I used a bar of soap with a small plastic cup to splash myself clean.
I was just finishing my bath one evening, preparing to dry off, when I felt a sharp pain in one of my toes. It was like being poked with a hot needle in two quick jabs. I looked down to see a scorpion crawling away from under the rubber mat I stood on. The striped, 6-centimeter-long creature clearly was not pleased about getting wet and stepped on.
Knowing that some African scorpions can be quite toxic (even deadly in rare cases), I killed it so I could show it to my local hosts for identification. My toe started to throb as I quickly got dressed. My hosts said the scorpion was relatively harmless and that I would feel better in the morning. I woke to an odd electrical sensation in my foot and a numbness that went up to my ankle, but fortunately this subsided over the next two days.
Lesson learned: Always check underneath the mat before taking a bath!
– Brendan Laurs
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