Manipueira, nature's safer solution proven to recover more gold from ore
than by using mercury, a deadly neurotoxin.
Scalable ESG-driven Climate Action Initiative
Our scalable climate action initiative is designed to replace the mercury uses in artisanal miner's ore processing and to eliminate their use of toxic cyanide salts in tailings waste remediation where mercury amalgams with the salts during cyanidation and providing mobility for mercury when discharged after cyanidation.
Using cassava plant extract as a lixiviant was an idea developed by Dr. Marcello Veiga P. Eng., (whom I quote throughout this description), Professor Emeritus University of British Columbia Norman B. Keevil Institute of Mining Engineering who along with Pariya Torkaman, conceived and coordinated the experiments combining conventional mechanical processes using gravity and centrifugal force to capture fine gold concentrate after milling, or from tailings ponds waste.
This data is detailed in their Publication “Leaching gold with cassava: An option to eliminate mercury use in artisanal gold mining”,
The use of cassava is proven and scientifically documented to recover more gold safely and sustainably than mercury amalgamation.
Bitter cassava, a cyanogenic plant is common in many Latin America ASG mining areas and is used to manufacture flour “manipueira” and make tapioca which in Brazil, is used to make beer.
“Bitter cassava has been sustaining millions of people in the world who produce flour”.
According to P. Torkaman et al, when crushed “the cassava plant liquid extract contains hydrogen cyanide generated from the hydrolysis of non-toxic cyanogenic glycosides which are substances intrinsically”. “These plants do not contain cyanide, but they generate it as a defense mechanism to intruders”.
“The free cyanide expelled liquid from the bitter cassava plant represents 30 – 40% of the root weight representing 267 milligrams of free cyanide per liter of extract. The indigenous name for this fluid is “manipueira” in Brazil which is recklessly disposed of on the ground around the mills, and when fermented, creates a nasty odor, and attracts insects.”
“Flour mills face a serious problem of disposing large amounts of “manipueira” (300 liters/tonne of the root)”
“The symbiosis of artisanal flour producers with artisanal gold miners can be an environmental win-win solution to reduce pollution from both sides.”