Science & Nature
Aug 1, 2017
Geologist Tshiamo Legoale, a 27-year-old South-African scientist, claims that statistics show that South Africa has circa 17,7 million tons of gold mining waste, that is, although the gold has already been dug out of that waste, "all this gold was mined out previously, but tiny amounts remain in the dumps" on particles so microscopic that it can't be harvested on any of the traditional ways of mining.
Her research on how it would be possible to retrieve that wasted gold granted her the FameLab award of the current year. The FameLab is an annual event that started on 2005 and is an international contest that awards scientists on several national finals (one was even hosted on the facilities of NASA, on 2015) until the international final round that each years occurs at the Cheltenham Science Fair, in the United Kingdom. The participants are judged not only based on the research they have been conducting but also on the excellency of how they are able to present that research, the judges analysing their clarity, content and communication skills, while on parallel the audience also votes on its favourite presentations. Tshiamo Legoale won on both votes, she was the favourite of the audience as well as of the judges, competing with 31 fellow scientists.
Legoale is researching methods to use wheat as an hiper-accumulator for gold or, using her own word, "to grow gold out of wheat", breaking new ground on the field of metallurgic research. On practical terms, by planting wheat on the gold mine dumps it will absorb the gold particles through natural enzymes on its roots, the gold will be absorbed by all parts of the plant except the seeds. That meaning: the stem and the leafs of the wheat can be used to harvest gold without that affecting the wheat grains, that still can be consumed as food without any risk.
The process, called phytoextraction, consists on the use of plants to purge the soils contaminated or polluted by inorganic substances such as chemical elements and mining waste. The plants extract those minerals on a completely natural way, without any negative effects on the environment, being that wheat can absorb gold on higher quantities than any other plant, the gold accumulated on the stem and leafs is then recovered through incinerating it and extracting the minerals out of the ashes.
Legoale, that is a researcher at Mintek, South-African company that is a world leader on metallurgic innovation, already begun her research as a pilot but Mintek is hoping to expand its use throughout the next five years, focusing now on how it will be possible to get a bigger quantity of gold on each harvest and also express the wish to witness the "human impact" of its use, be it through the use of the wheat's grain as food for the population, be it through the creation of jobs that this new type of crop on dumps may create. We have to highlight the social impact of Legoale's victory, being a young female South-African scientist and one of the three representatives of the African continent present at FameLab and there is hope that it can inspire more youngsters to embrace a career on the field of sciences on a continent that is still on its first steps as far as technological innovation is concerned.
Legoale Mintek's department is focused on small scale mining, with the purpose of creation jobs on marginalized communities through the use of natural ore, an extremely high number of South-Africans lives on villages, towns and cities on the proximity of an ore dump, being exposed to the risks of soils contaminated with minerals, having no jobs after the mines closed down and, taken to extreme poverty, they might engage on illegal mining, something extremely hazardous on abandoned mines. Her research hopes to contribute to solve these issues.