Did you know how the critical metal tantalum is mined and where?

The image shows a small-scale mining site in central Africa, in which both primitive underground (hard-rock) mining and the mining of secondary gravel deposits (right-hand side in image) takes place. Photo: Erik Jonsson/SGU.

A significant part of the global production of tantalum, together with some niobium and tin, is more or less the result of artisanal mining in the central African region.

The dark tantalum ore is separated manually from the other minerals Source: BGR [source: https://www.bgr.bund.de/EN/Themen/Min_rohstoffe/Rohstoff_forsch/LF_Herkunftrsnachweis_COLTAN_Newsletter01-2010.html [english].

Artisanal Mining is a common practise in many regions worldwide. Although some mines are run in a (in this context) relatively safe and responsible way, others, particularly in the eastern part of the Democratic Republic of Congo (DRC) are characterised by the absence of respect for human health and safety issues. The production of tantalum, niobium and tin ores (and to some extent also tungsten and gold) from such operations, has led to the use of the term ‘conflict minerals’ for the primarily produced oxide mineral concentrates. This is what has prompted new legislation on the responsible sourcing of raw materials (to be enforced in the EU by 2021) to try to mitigate the use of such ores. One of the tasks in the GeoERA FRAME project aim to highlight the potential for, and collates information on tantalum and niobium deposits in Europe.

Revisit the post on the discovery and use of tantalum here.