schmetterlich (asker) Mar 5, 2021:

Thank you for your resplies. According to the client, roca de estéril is waste rock. Thank you again.

Althea Draper Mar 5, 2021:

...also, http://repositorio.uchile.cl/bitstream/handle/2250/170594/Me... refers to them as different types of waste, "La industria minera de Chile está enfocada principalmente en el cobre en total 5.552,6 miles de toneladas finas reportadas en el 2016. Esto es solo una cara de la moneda, ya que paralelamente se genera una gran cantidad de material sin valor o con poco valor económico, denominado residuo minero. Dentro de estos residuos se encuentran: las escorias (provenientes del proceso de pirometalurgia), los ripios (residuos de la lixiviación del proceso de hidrometalurgia), el material sin o con poco valor económico denominado estéril (almacenado en botaderos) y los relaves (originados principalmente de la etapa de flotación). Estos dos ultimos constituyen el mayor problema debido a su cantidad y volumen"

Althea Draper Mar 5, 2021:

I see what you mean. My problem is that I think the word for tailings is 'relave'. You'll see that 'relave' and 'estéril' are both waste but are two different types of waste. The 'relave' is from the crushed ore bearing layer which is processed to retrieve the mineral, and the 'estéril' is from the sterile layer that contains no ore (or an amount of ore that is below what it is profitable to retrieve). Figures 3 and 4 in this paper shows where the 'estéril' is found https://www.researchgate.net/publication/327000730_Manejo_es... . IATE searches show https://iate.europa.eu/search/standard/result/1614961270735/... and https://iate.europa.eu/search/standard/result/1614961254767/... . Dictionary entries show https://dle.rae.es/relave and https://dle.rae.es/estéril?m=form ...

philgoddard Mar 5, 2021:

Althea You may have a point, but I believe definition 4 supports my answer. Could it mean tailings AND overburden?
http://glosarios.servidor-alicante.com/mineria/esteril

Althea Draper Mar 5, 2021:

I'm not sure that this is tailings. Going by this research paper https://www.researchgate.net/publication/327000730_Manejo_es... and this presentation http://cuencas.fcien.edu.uy/cursos/materiales/residuosmineri... , to me it looks like 'rocas de estéril' are the overburden - see https://en.wikipedia.org/wiki/Overburden . "Overburden is the material that lies above an area that lends itself to economical exploitation, such as the rock, soil, and ecosystem that lies above a coal seam or ore body. Overburden is distinct from tailings, the material that remains after economically valuable components have been extracted from the generally finely milled ore. Overburden is removed during surface mining, but is typically not contaminated with toxic components. Overburden may also be used to restore an exhausted mining site to a semblance of its appearance before mining began."