Emerald Mines in Colombia

Emerald Mines in Colombia

The home of the most beautiful Colombian emeralds is in the Eastern Cordillera (Oriental) between Cundinamarca and Boyacá in the eastern ridge of the Andes Mountains. The tree main mining areas are Chivor, Muzo and Coscuez. 

Before the arrival of the Spaniards in 1499, the indigenous people of Boyacá had already begun the extraction of the emeralds in the region. Archeologists estimate that the native people commercialized these gems in 1000 AD. Once the Spaniards had established in Colombia, in the different regions, they exploited the gems that ended in the hands of European aristocrats and mogul governors of India. 

During the colonial period, miners extracted emeralds by following the veins end because of the mine issues some works were abandoned in the mid-1600’s. Work was retaken nearly two centuries later and using more modern techniques at the Coscuez mine. These works led to the discovery of a mineral called parasite, a rare fluorocarbonate of cerium. Little has been said about the Coscuez mine activity lately. It has been repeatedly worked, abandoned, and reopened. 

As for the Muzo mine, it has a long history that started when it produced most of the emeralds in the region in the early 1900’s and it was eventually taken over ECOMINAS to try to control illegal mining and back marketing of emeralds. This was a success due to the increase in the exported emeralds. 

The government control of the Colombian mines has been of help to bring peace into these areas where there was conflict between the drug cartels, government, and emerald mining families. 

Regarding the geological setting of the emeralds, there are three main types of deposits where they can be formed: magmatic-metasomatic; sedimentary – metasomatic and metamorphic – metasomatic. Colombia’s emerald deposits are sedimentary – metasomatic. Most of the emeralds are hosted predominantly in shales of the Cretaceous (formed more than 65 million years ago), which makes them unique in the world. The tectonics of the area created the perfect blend for the emeralds to form. 

About the mining methods used to exploit the emeralds, it has changed over the time, some of the techniques used are open-cut mining, tunnelling and use of heavy machinery, as open pit and underground mines.  

The open-cut mining was used mostly because of the steep slopes of the formations covered by the jungled that could only be worked in great terraced banks. The limestone and shale make it easy to remove the emerald crystals. The stones are then separated into several grades according to color, size, transparency, and impurities.  

Tunnelling was used as of 1987 in Muzo mine because of the very limited gems found near the surface. Mining of emeralds seem to be a very manual method and there were even some “guaqueros” (treasure hunters) that would dig through the debris in the hopes of finding emeralds missed by the workers. Tunneling method has limited the number of treasure hunters because of nature of the technique. 

Colombia is second on exporting emeralds just after Zambia. More than 80% of the exports go to the USA, Hong Kong and Switzerland. 

The world of Colombian emeralds is fascinating, however there is very limited information on the production and mining methods used by the mining companies in Colombia. It would be important that companies publicly share their discoveries with the world. 

 

References: 

Dice, S., & Dice, O. M. (2020, May 11). Minería de esmeralda en Colombia: Minería en Línea. Retrieved from https://mineriaenlinea.com/2020/04/mineria-de-esmeralda-en-colombia/ 

Ringsrud, R. (1983). The Coscuez Mine: A Major Source of Colombian Emeralds. Retrieved from https://www.gia.edu/doc/The-Coscuez-Mine-A-Major-Source-of-Colombian-Emeralds.pdf 

Colombia Emerald Mines – A Guide to Colombian Emerald Mining. (2021, May 12). Retrieved from https://www.emeralds.com/education/mining-locations/colombia-emerald-mines/ 

Colombia Emeralds: Investment Sought as Exports Spike. (2021, June 11). Retrieved from https://www.bizlatinhub.com/colombia-emeralds/ 

Jewellery Appraisers of the World. (n.d.). Colombian Emeralds from the Muzo, Coscuez and Chivor mines. Retrieved from https://www.ja-world.com/consumer/emeralds-from-muzo-coscuez-chivor.html 

Mining Sustainability in Peru

Mining Sustainability in Peru

Global trends indicate the expansion of mining in these last few months. The mining industry in Peru has registered an increase of +50.0% according to the latest statistics (National Statistics Institute of Peru, INEI) and given the increase in the gold price this brings a strong economic growth in different countries all over the Americas.  

Mining has been a sector in Peru that contributes 14% to the country’s Gross Domestic Product and that provides a significant national economic support.  

The current mining laws promote a balance between the mining activities and the conservation of the natural resources. However, most of the time the lack of responsibility from the state agencies limits the sustainable development of the country.  

The commission for sustainable mining development provides public policies to highlight the benefits of renewable energy within mining activities in Peru and has identified five core components that make a sustainable country: social environment, citizenship, diversity and territory, environmental management, regulatory improvement, tax contribution and use of mining resources, and informal and illegal mining. 

Regarding the environmental impacts and usage of renewable energies there is still some work that can be done. Especially for the carbon footprint that mining leaves behind during mining development. The mining industry consumes already 56% or the national energy production in Peru and the use of these environmentally friendly energies are an attractive option for mining companies in the last few years. 

There have been improvements in the renewable energies sector that have been done mostly in developed countries and mining companies benefit of the new technologies which make mining more sustainable. 

The international council on Mining and Minerals (ICMM) suggests the use of renewable energies and Peru’s renewable energies represent only 4.8% of national production. Peru’s natural renewable resources have not been developed to its maximum potential (solar potential and wind speeds).  

Today’s renewable energies also depends on the impulse of the private sectors that indirectly contribute to energy decarbonization. Some mining companies already incorporated solar and wind solutions to provide energy to their mining activities. The inclusion of this type of clean energy can also bring a community benefit because of the infrastructure developed in the mining areas. 

Mining could have adverse effects on the living conditions of people through the impact on land and water resources. These effects increase the uncertainty of mining concessions, as well as the misinterpretation of information received in the social entities which could obstruct the exploration in remote areas. 

The sustainability of the country highly depends on the social institutions created to manage relationships between mining, natural resources and the communities directly affected. 

Some changes have been generated in different sectors but there are also challenges for local governments mostly related to social conflict. Institutions can be more effective and create progress that will foster the economic growth of the country. 

 

References: 

Institutional Challenges For Mining and Sustainability in Peru 

Anthony Bebbington-Jeffrey Bury – https://www.pnas.org/content/106/41/17296 

A Sustainable Approach To Mining in Peru 

https://fsr.eui.eu/a-sustainable-approach-to-mining-in-peru/ 

Sector Minero De Perú Se Dispara 82% En Mayo – .:: Minería En Línea 

https://mineriaenlinea.com/2021/07/sector-minero-de-peru-se-dispara-82-en-mayo/ 

Long Hole Mining Method Modeling

Long Hole Mining Method Modeling

A quick google search about this topic leads to results such as: long holes sublevel stoping, transverse longholestoping, long hole shrinkage stoping method, sublevel open stoping, and others. All these results resume to Shrinkage stoping and long hole stoping which happen to be the most used methods in the mining industry nowadays.  

Shrinkage stoping is used widely on steep ore bodies (70-90) and the holes depart from the bottom upwards, it could be backfilled or left empty depending on different factors.  

Longholestoping is a very popular method in underground mining for blasting a sequence of stopes in metalliferous mines. The holes are drilled according to a predetermined pattern designed by a mining engineer. This method is one of the most productive ones and covers a variety of ore thicknesses and dips (0 – 90).  This method unavoidable adds dilution (20%), but it offers advantages such as very high productivity and efficiency because the blasted rock falls into a supported drawpoint that is excavated below the stope bottom, and which allows for the removal of the blasted rock using remote control LHD or rail cars for longer transport. The method also offers mid-range mining cost and low hazardous conditions (easily ventilated).  

 

When it comes to modeling and putting this on paper there are many variables that are determinant on every single stage of the method (from planning the drill and blast patterns, to scanning the cavity and using different software for modeling representative solids in 3D). Currently, there are many software solutions in the industry for these different stages, but most of them do not encompass all the needs of a mining engineer.  

There are three main drill patters that are widely used by mining engineers for sublevel stopping: ring drilling, fan drilling and parallel drilling. These popular patterns can all be easily modeled with the use of Promine’s “Drill and Blast Underground” module.   

Once the blast sequency has been determined, it is time to blast! Once blasted we remove the rock and send it to the milling plant to extract the material of interest. 

 

Mining professionals depend on specific technologies through every single stage of development and production of a mine. The need for these specific technologies creates a particular challenge for software and hardware companies which must quickly adjust to the changing needs of the mining professionals. The mining industry also must constantly be adapting to new developments in mining methods, improved technologies and ever more demanding professionals. Whether we are users or developers, we all face problems that range from the simple to the complex and some of these problems will require the expertise of knowledgeable mining professionals that are part of a specific niche (programming, mining, geology, survey areas or others).  

 

When working as users during the planning of a drill pattern, we want everything to be simple and straightforward.  As users in an ideal world the interface of our mining software would contain all the features that would allow us to do anything, but as developers, we are trying to deliver only what clients need for their planning so unavoidably, the software will have certain limitations on the interface.   

 

As a software company we get many requests to integrate new features and improvement into our program and we are very happy to deliver all of these to our clients. For example, a software solution was completely integrated in our interface to allow the users to scan on real time the relative susceptibility and EM conductivity of the rock in a production hole by using a probe (SSW system from Instrumentation GDD).  The results are then displayed on a drawing of a drill pattern design.     

 

Image: Real time survey generated in Promine-AutoCAD using GDD SSW instrument.  

 

Our senior software developer, Pier-Alex Côté-Sarrazin, has commented that “The challenges on programming certain new features for external applications in our interface can vary”.  These challenges range from having poor content documentation for the application, to understanding how to establish communication from the hardware to the software.  Additional challenges are understanding which are the communication ports being used by the target application and the simple fact that an old technology is no longer compatible with a new technology, something we have all experienced with devices such as a very old iPod that you want to synchronize with the most recent version of iTunes and are not able to do it.   

 

Some of our clients’ requests have involved very particular challenges and changes that our software department has been ready and eager to tackle. Mining software companies such as Promine are constantly developing new solutions to rise to the challenges posed by ever evolving mining methods.  We adapt to these market needs by applying state of the art technology and the latest know-how when it comes to developing the solutions our customers expect from us.  

 

References: