Safer Gold Mining Promoted by Prof. Norman

In response to this problem, David I. Norman, professor of geochemistry at New Mexico Tech, has developed a simpler, safer method of extracting gold and he is expounding the new refining technique in undeveloped countries and elsewhere around the world by illustrating it through videotaped tutorials.

The process really is quite simple: As Lauren Bacall once succinctly put it, "Just put your lips together and blow."

The method demonstrated on the video involves first panning out a gold-rich slurry from muddy rivers or streams and then drying the remaining concentrates. Many of the metallic grains which are not gold are removed from the concentrates with a magnet. The lighter sand granules are then separated from the remaining, heavier gold particles by blowing, brushing, and tapping the sand off of a white sheet of paper. What remains on the paper after this procedure is a tidy, little pile of nearly pure gold dust, ready for sale.

The only tools required for this quick and easy procedure are a large white sheet of paper, a small paint brush, a magnifying glass, a magnet, and a small pointed object, like a needle or ice pick, to pick out the smaller sand grains.

The 20-minute-long training videos currently are available in English and Spanish versions. Editions in Portuguese--for Brazilian gold miners--and African languages also are planned to be produced and distributed soon.

"Gold miners in these poorer countries who use the mercury amalgam process typically throw away an amount of mercury equal to or greater than the amount of gold they produce," Norman points out. "In Ghana alone, an estimated 10 tons of gold is produced each year by small-scale gold miners, so you can begin to get a general idea of the extent of the problem."

In Ghana and other African "Gold Coast" countries, as well as in the Amazon rain forests of Brazil, the young men who labor in the gold fields--a majority of them uneducated, most of them illiterate--harbor little or no concept of the risks involved with using this highly poisonous liquid metal to separate particles of gold from river sediments.

In mercury amalgam goldmining processes, mercury often pollutes the nearby rivers and streams where most of the mining operations are carried out. In the water, metallic mercury changes into methyl mercury, a persistent, lingering form of mercury which builds up in food chains, ultimately accumulating in fish--a staple food of people who live near those same waterways.

A gaseous, easily inhaled, form of mercury also is often released directly into the surrounding air as miners heat up mercury/gold mixtures in open vessels to vaporize any residual mercury left by the amalgamation process.

After prolonged exposure to mercury, African gold miners typically develop a sort of "miner's palsy," uncontrollable body tremors which, along with tunnel vision and other neurological disorders, signal the intermediate stages of mercury poisoning.

Norman can attest to that: he has encountered countless numbers of miners afflicted in such a manner by the slow-acting poison on his numerous research trips to Ghana.

In its advanced stages, mercury poisoning leads to a marked increase in birth defects, blindness, permanent brain damage, dementia, and, eventually, death.

Illustrative footage used in the training videotapes, which espouse the safer and less expensive (a teaspoon of mercury sells for about $5 to $10) method of gold refinement, was filmed last summer on location in Ghana gold camps under actual field conditions.

Bill Shell, lead instrumentation technician and photographer with New Mexico Tech's Energetic Materials Research and Testing Center (EMRTC), served as chief videographer for the project, often having to trudge through rain-swollen, waist-deep streams to videotape many of the location shots.

Shell also spent many days "at home" working in EMRTC's production studio, adding graphics and doing all the editing required to complete the training video.

Ray Tobin, associate safety officer at EMRTC, provided the narration for the English version of the training video, "Separation of Gold from Alluvial Concentrations."

And, Rafael Lara-Martinez, assistant professor of foreign languages at New Mexico Tech, provided the Spanish translation.

Funding for the project was provided in part by a grant from the U.S. Department of Agriculture, the U.S. Agency for International Development, and also through an organization associated with Ghana's University of Science and Technology School of Mines.

One of Norman's research associates at the University of Science and Technology, Henry Appiah, served as technical advisor and consultant to the project.

Norman adds that he and his colleagues hope to soon produce and release another training videotape which will focus on using a more efficient sluice design in small-scale gold mining operations.

"Ghana brings in about $150 million a year from small-scale gold mining operations," he points out, "so even 10 percent more efficiency means a major boost to their economy."

-NMT-

(George Zamora)