On the reddish, glittery mud the Inca used for perfecting their stone masonry

Citation

Helmut Tributsch, On the reddish, glittery mud the Inca used for perfecting their stone masonry(2017)SDRP Journal of Earth Sciences & Environmental Studies 3(1)

Abstract

Due to its impressive appearance, Inca masonry, which mostly consists of volcanic, silica containing rock material, has received much attention. A high level of understanding has consequently been reached of the diverse working steps and tools applied. An exception is the reddish mud, “llancac alpa” in the quechua language, and the “gold”, mentioned by early chroniclers as mortar which fitted the stones and later disappeared. Such techniques were related to folklore and not taken seriously. This study tries to understand them and the question was asked: did Inca builders have access to very acid mud? They did, and used the acid mud from their mines, which generated sulphuric acid through bacterial oxidation of pyrite (fools gold). It reaches an acidity of up to pH = 0.5, which is 104 times more acid than humic acid which is known to weather silica containing rocks via silica gel to the clay mineral kaolin. This acid mud allowed dissolving and softening the rock material superficially to a viscoelastic silica gel. The process could be further enhanced more than tenfold by addition of (oxalic acid containing) plant sap, a skill suggested from popular tradition. In special cases moderate heating of crushed pyrite in gaps between chiselled stones generated additional hot sulphuric acid. Where the stone to stone contact transmitted weight, pressure dissolution in the acidic environment removed material, and silica precipitation regenerated material in cracks and pores elsewhere. It is attempted to reconstruct how the Inca builders applied the silica gel technology for shaping stones, for polishing and fitting them. The appearance of shiny and glassy Inca stone junctions and interfaces is explained via solidification of in-situ generated or additionally added silica gel. Modern processes for conservation of stone monuments against environmental deterioration have independently developed similar silica gel based technology.

Key words: Inca masonry; surface treatment; silicate dissolution; acid mine water; bacterial leaching; stone restoration; pyrite

References

  1. Aggarwal, P.; Pratap Singh, R.; Aggarwal, Y. (2015) Use of nano-silica in cement based materials-A review. Cogent Engineering, [2], 1078018. . https://doi.org/10.1080/23311916.2015.1078018

    View Article           

  2. Aizenberg, J., Sundar, V. C., Yablon, A. J., Weaver, J. C., and Chen,G., (2004), Biological glass fibers: Correlation between optical and structural properties, PNAS 2004 101 (10) 3358-3363; doi:10.1073/pnas.0307843101

    View Article           

  3. Andrea, D. (2002), , retrieved, 14/11/ 2016)

    View Article           

  4. Angevine C. L. and Turcotte D. L., (1983) Porosity reduction by pressure solution: a theoretical model for quartz arenites, Geol. Soc. Am. Bull., vol. 94, 1129?1134 (1983) 94<1129:PRBPSA>2.0.CO;2

    View Article           

  5. Barman A.K., Varadachari C.,Gosh, K, (1992), Weathering of silicates by organic acids I. Nature of cation solubilization, Geoderma 53,45-63 90020-8

    View Article           

  6. Barnab? Cobo (1953) Historia del Nuevo mundo, book 14, chapter 12

  7. Barnett, R.L., Kerrich, R., (1980), Nature 283,185-187

    View Article           

  8. Bennett P.C., Casey W. (1994) Chemistry and Mechanisms of Low-Temperature Dissolution of Silicates by Organic Acids. In: Pittman E.D., Lewan M.D. (eds) Organic Acids in Geological Processes. Springer, Berlin, Heidelberg,

    View Article           

  9. DOI

    View Article           

  10. Bl?zquez, B. H. (2003), Las Piedras de Plastilina, Revista: Vivat Academia 46, (retrieved: 25/11/2017)

    View Article           

  11. Bowes, P.C., (1952), Note on spontaneous heating and ignition in iron pyrites; Fire research notes 39; (retrieved 29/11/2017

    View Article           

  12. Burke,S.P.,Downs, R.,(1938) Trans. Amer. Inst. Min. Met. Eng. 130, 425

  13. Cieza de Le?n, Pedro (1553), La Cr?nica del Per?, Buenos Aires, 1945,; Secunda parte de la Cronica del Peru, Instituto de Studios Peruanos, Lima (1967), chapter 27; Parte Primera de la Cronica del Peru. Edici?n Espasa-Calpe, Madrid 1932, 1962, chapter 44

  14. De Jong Peter & Christopher Jordan, (2012), Evidence of Vitrified Stonework in the Inca Vestiges of Peru, Blog: retrtieved febrary 13, 2016.

    View Article           

  15. Drever, J. I. (2005), Surface and ground water, weathering and soils, p. 175

  16. Drever, J. I., L. L. Stillings. (1997). The role of organic acids in mineral weathering. Coll Surf 120:167?181 03720-X

    View Article           

  17. Franceschi V.R., Nakata P.A. (2005), Calcium oxalate in plants: formation and function, Annu. Rev. Plant. Biol. 56, 41-71, PMid:15862089

    View Article      PubMed/NCBI     

  18. Garcilaso de la Vega (El Inca), (1609) Comentarios Reales de los Incas. 6th book, chapter 1, 7th book, chapter 27; Madrid 1723 or Edition Carlos Aran?bar editor), Fondo de Cultura Econ?mica, Ciudad de M?xico 1991, ISBN 968-16-4892-7; : 2005, ISBN 968-16-4893-5.,

  19. Huang, W.H., Keller, W.D.,(1970) Dissolution of rock-forming silicate minerals in organic acids: simulated first-stage Weathering of fresh mineral surfaces, The Americal Mineralogist, 55, 2076-2094

  20. Keatinge, R.W. (1988). Peruvian Prehistory: An Overview of Pre-Inca and Inca Society. Cambridge University Press. PMid:3384604

  21. Fowler A. C. and Yang X. S.,(1999), Pressure solution and viscous compaction in sedimentary basins, J. Geophys. Res., B104, 12898?12997 (1999).

    View Article           

  22. Lara Monge F. (1906). La metalurgia del oro y la plata en el Peru antiguo, en la colonia y en las culturas Inca y Pre-Incas, I Congreso International de Mineria y Metalurgia en el Contexto de la Historia de la Humanidad: Pasado, Presente y Futuro . Mequinenza 6-9, julio 2006. P-09, pp. 105-116; www.sedpgym.es/descargas/libros_actas/MEQUINENZA_2006/Mequinenza_31.pdf

  23. Lechtman, H. (1991). "The Production of Copper-Arsenic Alloys in the Central Andes: Highland Ores and Coastal Smelters?". Journal of Field Archaeology 18: 43?76. doi:10.1179/009346991791548780.

    View Article           

  24. Livermore, H.V., (1966), Royal Commentaries oft the Incas and General History of Peru, by Garsilaso de la Vega, El Inca, University of Texas Press, Austin & London

  25. Mason, J.A., (1979), The Ancient Civilization of Peru, p. 162, 274, Penguin Books, New York 1979 Protzen, J.-P. (l986). Inca stonemasonry. Scientific Amer. 254: 94-105.

  26. Protzen, J.-P. (1993), Inca Architecture and Construction at Ollantaytambo. Oxford University Press. New York. 1993.

  27. Protzen, J.-P. and Nair, S.E. (1997). Who Taught the Inca Stonemasons their Skills? A Comparison of Tihuanaco and Inca Cut-Stone Masonry. Journal of the Society of Architectural Historians: 52:2, 146-167.

    View Article           

  28. Protzen, J.-P., Nair, S.E., (2000), "On Reconstructing Tiwanaku Architecture." Journal of the Society of Architectural Historians. September 2000. 358-71.

    View Article           

  29. Rojas-Chapana J., Tributsch H. (2001), Biochemistry of Sulfur Extraction in Biocorrosion of Pyrite by Thiobacillus ferrooxidans Biohydrometallurgy and the Environment toward the Mining of the 21st Century,Proceedings of International Biohydrometallurgy Symposium IBS-99, Madrid June 1999 Editors: R. Amils and A. Ballester; Elsevier, Process Metallurgy 9A, Part A (1999) 597-605 and Hydrometallurgy 59 (2001) 291-300

  30. Rojas-Chapana J., Tributsch H.,(2000), Bio-Leaching of Pyrite accelerated by Cysteine, Process Biochemistry 35 (8) (2000) 815-824 00142-9

    View Article           

  31. Rojas-Chapana J., Tributsch H., (2004), Interfacial activity and leaching patterns of Leptospirillum ferrooxidans on pyrite, FEMS Microbiology Ecology 47 (2004) 19-29 00221-6

    View Article           

  32. Rutter, E. H. (1976). "The kinetics of rock deformation by pressure solution". Philosophical Transactions of the Royal Society A 283: 203?219. doi:10.1098/rsta.1976.0079. JSTOR 74639.

    View Article           

  33. Rutter, E.H. (1983). "Pressure solution in nature, theory and experiment.". Journal of the Geological Society, London 140 (5): 725?740. doi:10.1144/gsjgs.140.5.0725. Retrieved 24 November 2010.

    View Article           

  34. Thompson, D.E. (1980), Book Review: Tnca Architecture, Science 210, 779 PMid:17739543

    View Article      PubMed/NCBI     

  35. Tributsch H., Rojas-Chapana J.(2000), Metal Sulfide Semiconductor Electrochemical Mechanisms Induced by Bacterial Activity, Electrochimica Acta, 45 (2000) 4705-4716 00623-X

    View Article           

  36. Tributsch H., Rojas-Chapana J. (2006), Bacterial Strategies for Obtaining Chemical Energy by Degrading Sulfide Minerals, in: The Practice, Theory and Microbiology of Biomining, Springer Verlag; ed. by Douglas E. Rawlings, D. Barrie Johnson, Chapter 13 (2006) 263-280

  37. Watkins, I. 1990. How Did the Incas Create Such Beautiful Stonemasonry?" in "Rocks and Minerals" Vol. 65 Nov/Dec 1990.

  38. Winmill, T.F., (1916),Trans. Inst. Min. Eng. 51,500

  39. Zendri, E.; Biscontin, G.; Nardini, I.; Rialto, S. (2007) Characterization and reactivity of silicatic consolidants. Constr. Buildi. Mater., [21], 1098?1106.

    View Article           

  40. Zornoza-Indart, A.; L?pez-Arce, P. (2016) Silica nanoparticles (SiO2): Influence of relative humidity in stone consolidation. J. Cult. Herit., [18], 258?270.

    View Article           

We publish articles under Creative Common License (CC-BY) that ensure that all published papers are immediately and permanently available online for everyone, worldwide.
Submit Manuscript