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Massey University 

Entanglements and Disentanglements: 

A Posthuman Approach to Mercury Use in 
Artisanal and Small-Scale Gold Mining in 

Antioquia, Colombia 

A thesis presented in partial fulfilment of the requirements for the degree of Master of Arts 
in Social Anthropology at Massey University, Palmerston North, New Zealand 

Thomas Jonathan Robertson 

2016 



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Acknowledgements 

Producing this thesis was not an individual exercise, and was only possible with the 

support of my friends, family, colleagues, and last but not least, my research 

participants.  

I would like to thank the Sasakawa Young Leaders’ Fellowship Fund which believed 

in me enough to generously offer to fund this research. 

I would like to thank my supervisor Dr Trisia Farrelly for her guidance, support and 

her immense intellectual contribution to this thesis. I would also like to thank my 

supervisor Associate Professor Glenn Banks for his advice and contributing his 

immense expertise on mining. It has truly been a privilege to be able to work with 

these academics and learn from their experience. 

I would like to thank my close friend Gabriel Aramburo Gómez and his parents Luz 

and Gabriel for giving me a place to stay during my fieldwork, for their continuous 

friendship and support, and for helping me to learn Spanish. I would also like to 

thank my close friend Esteban Villa Gómez, who helped and supported me 

throughout my fieldwork. I am deeply grateful. 

I would like to thank my parents, Lindsay and Anne Robertson, for their continued 

support in producing this thesis and their belief in my ability to do so. I cannot 

thank them enough. 

I would like to thank the countless people who assisted me in my fieldwork, both in 

big and small ways. Most importantly, I would like to thank Oseas García, Carlos and 

Catrina Paez, Penelope Dransart, Diana Cardenas, Juan Carlos Díaz, Oscar Jamie 

Restrepo, Santiago Cárdenas Herrera, Jairo Emilio Vélez, Carolina Arbelaez, and 

Ester Galeote Nadal.  



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Finally, I would like to thank the miners, gold processors and miners’ association 

members of Antioquia who co-produced this research. They made this thesis 

possible, and it is to them that this thesis is dedicated. Carlos, Esteban, Miguel, 

Felipe, Mateo, David, Santiago, Juan, Ramiro Restrepo, Marco Antonio, and the 

others not directionality mentioned here, I cannot thank you enough for your 

kindness and assistance. I hope this thesis can draw attention to the challenges 

which you are working to overcome.  



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Abstract 

This research uses qualitative research techniques and posthuman theories to 

investigate the dynamic relationship between artisanal and small-scale gold miners 

and mercury in the context of Antioquia, Colombia. This is done to contribute to 

understandings of, and inform potential solutions for, the global environmental 

problem that is mercury pollution from artisanal and small-scale gold mining 

(ASGM). Miners come to know mercury through practices, and through these 

practices, mercury comes to be co-constitutive of an informal ASGM industry. 

Mercury provides an easy yet profitable mode of gold extraction with limited 

capital expenditure. Eliminating the use of mercury means a re-constitution of 

ASGM as a formal industry with higher levels of capital investment, new actors and 

a shift to a more representational approach to knowing materials. The use of toxic 

mercury and an increase in the enforcement of mining legislation are framing 

miners as illegal. Formal, responsible mining is becoming a dominant reality, and 

informal miners who resent being labelled illegal are working to transition to this 

reality. Miners’ experiences of this transition vary greatly, and this variation can be 

explored through the lens of ecological habitus. Many miners are using mercury 

elimination to perform good citizenship by mining responsibly, introducing a 

performative aspect to formalisation. Nevertheless, miners still face significant 

challenges to formalisation. As a result, many miners have had to become 

subcontractors for large-scale mining companies, entering exploitative relationships 

with which mercury, through its absence, is complicit. Taking this approach towards 

understanding the relationship between miners and mercury has helped to resolve 

the conflict between material and social deterministic views of the practice of 

mercury use, and linked mercury to a wider political context, which is a necessary 

consideration for a collaborative approach with miners to eliminate mercury. 

Keywords:  

Artisanal and small-scale gold mining; ASGM; mercury; Colombia; anthropology; 

posthumanism; entanglements; politics of materiality; performativity; informality. 



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Table of Contents 

ACKNOWLEDGEMENTS I 

ABSTRACT III 

TABLE OF CONTENTS IV 

LIST OF ILLUSTRATIONS AND TABLES VII 

CHAPTER 1: INTRODUCTION 1 

CHAPTER 2: LITERATURE REVIEW 6 

The Global Problem of Mercury Pollution 6 
The Minamata Convention 9 

Mercury Reduction Themes 10 
Alternatives to Mercury for Gold Extraction 10 
Appropriate Technology 11 
Education 11 
Formalisation 12 
Social Dynamics 13 

The Artisanal and Small-Scale Gold Mining Industry 13 

The Anthropology of Mining 15 
The Anthropology of ASGM 16 

A Theoretical Toolbox 17 
Deleuze and Guattari 18 
Posthumanism 19 
Bourdieu and Ecological Habitus 23 

Conclusion 24 

CHAPTER 3: THE CONTEXT OF ANTIOQUIA, COLOMBIA 26 

Mercury Use in Antioquia 26 

Colombia 28 
Antioquia 29 
Medellín 31 
Caucasia 32 
Segovia 33 
El Bagre 35 



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Gold Mining in Antioquia 35 
Scale and Economic Significance of ASGM 36 
Mining and Armed or Criminal Groups 37 

Informality 38 
Formalisation Initiatives 39 
Legality and Supply of Mercury 40 
Enforcement of Mining Legislation 40 

Mercury Reduction Initiatives 41 

Conclusion 42 

CHAPTER 4: METHODOLOGY 44 

Fieldwork Methods 44 
Interviews 48 
Purposive Observation and Deep Hanging Out 49 
Legal Seminars and Miner Training Centre Visits 50 

Ethical Considerations 51 

Positioning Myself within the Field 52 

Introducing my Key Research Participants 56 
Carlos 56 
Esteban 57 
Miguel 57 
Felipe 57 
Mateo 58 
Juan 58 
Santiago 59 
David 59 
Other Participants 60 

Conclusion 60 

CHAPTER 5: ENTANGLEMENTS WITH MERCURY 62 

Alluvial Open-Pit Mining 63 

Dredge-Based Placer Mining 66 

Hard Rock Mining and Gold Processing Workshops 67 

Gold Buying Shops 75 

Tradition, Custom, and the Nature of Change 78 

Awareness of Mercury Poisoning 80 



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ASGM: A Performed Entanglement of Miners and Mercury 81 

Conclusion 84 

CHAPTER 6: DISENTANGLING MERCURY 86 

Dredge-Based Placer Mining 87 

Alluvial Open-Pit Mining 96 

Hard Rock Mining 100 

Gold Processing Workshops 101 

Gold Shops 103 

A New Mode of Education in El Bagre 108 

Conclusion 109 

CHAPTER 7: THE POLITICS OF DISENTANGLING MERCURY 110 

Formalisation 111 

Formalisation through Subcontracting to LSM 114 

Alluvial Open-Pit Mining 119 

Dredge-Based Placer Mining 123 

Processing and Sales 124 

Mercury as a Discursive Material 126 

Conclusion 128 

CHAPTER 8: CONCLUSION 130 

REFERENCES 135 
 

 

 



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List of Illustrations and Tables 
 

Figure 1: Map of South America, with Colombia highlighted (Google, n.d.-b). ..................... 29 
Figure 2: Map of Colombia, with Antioquia highlighted (Google, n.d.-a). ............................. 30 
Figure 3: Map of Antioquia, with fieldwork locations marked (National Geographic, n.d.). 31 
Figure 4: Monument outside the bus station in Caucasia. .................................................... 32 
Figure 5: Monument in the central plaza of Segovia. ............................................................ 34 
Figure 6: Interview/meeting numbers and types of participants. ......................................... 47 
Figure 7: The ball mills in Santiago’s workshop. .................................................................... 69 
Figure 8: A closer view of the ball mills. ................................................................................ 70 
Figure 9: A disappointingly small ball of mercury-gold amalgam. ......................................... 70 
Figure 10: Cyanide storage tanks. .......................................................................................... 74 
Figure 11: Cyanide extraction in concrete pools. The planks to the rear are used as a 
walkway. ................................................................................................................................ 74 
Figure 12: Cyanide pools in the tailings outside. The visible buildings are residential. ......... 75 
Figure 13: The fume hood where the amalgam is burned. ................................................... 76 
Figure 14: Inside the fume hood. ........................................................................................... 77 
Figure 15: Mercury for sale in Caucasia, and the measuring syringe. ................................... 77 
Figure 16: Sluice box. ............................................................................................................. 88 
Figure 17: Trommel. ............................................................................................................... 89 
Figure 18: Centrifugal concentrator. ...................................................................................... 89 
Figure 19: Spiral pan. ............................................................................................................. 90 
Figure 20: Gemini table. ......................................................................................................... 90 
Figure 21: Fume hood leading to the retort. ....................................................................... 105 
Figure 22: Respirator mask. ................................................................................................. 106 
Figure 23: Face protection. .................................................................................................. 106