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View Full Version : Oro Verde or Green Gold

Geo Jim
01-03-2013, 10:21 AM
I read on www.mining.com today of a "Green Gold" non-chemical substitute to using mercury. Apparently it has something to do with using balsam leaves to float the light rock particles off. So I Googled Green Gold and discovered this website. This website is beautifully done and very interesting, but nothing about using balsam leaves. Here it is:http://www.greengold-oroverde.org/loved_gold/

I am guessing the balsam tree leaves that they may be using are related to the balsam poplar, or cottonwood trees we have in North America. Perhaps there is a fine gold recovery technology that I have not heard of in Alaska placer mining scenes.

Check out the website and their mining video for a quick lesson in their artisanal mining.
Geo Jim

Geo Jim
01-03-2013, 11:23 AM
Here is the article on www.mining.com that refers to the balsam flotation thing:

Colombia hopes to achieve ecologically sound gold production by means of the Oro Verde ("Green Gold", movement, which pays small-scale miners a significant premium for the adoption of environmentally friendly processing techniques.

The World reports that miners in the northern Colombian department of Choco have started to turn to a traditional African technique for the extraction of gold which employs natural materials in lieu of mercury.

Miners use balsa tree leaves to produce a soapy film when washing the gold in water. The film traps lighter minerals, effectively separating them from the heavier flakes of gold.

The traditional technique was handed down to small-scale miners in the region by their African forbears and enables them to forgo the use of mercury during the extraction process.

The use of mercury by small-scale miners has already inflicted a heavy environmental toll in some of Colombia's key gold producing regions, leaving large swaths of jungle barren and contaminated while also damaging local water systems.

As part of the Green Gold movement groups such as UK-based Fairtrade and Fairmined are paying a premium of 15% to miners who employ environmentally friendly processes. Fairtrade and Fairmined have plans to introduce similar measures to other parts of Latin America, as well as Africa and Asia.

The movement faces considerable difficulty, however, with mercury-free gold mining requiring far greater time and effort in exchange for smaller profits, even when the generous premiums are included. So far only 1,400 miners in Colombia, Peru and Bolivia have signed up with the Oro Verde movement.
Geo Jim

Geo Jim
01-03-2013, 11:42 AM
Googling "green gold" produces a plethora of different results from jewelry to labeling, libraries, green logging practices that is somehow golden, glassware, consulting...oh my. I did not intend to spend my day this way. I better start googling "balsam flotation".

"Balsam flotation yields that pine oil is used for froth flotation and there is a product called Canada balsam that is used in mineral processing.

WOW, I am onto something now, "balsam trees used in flotation" I am getting nowhere now.
Geo Jim

01-03-2013, 07:03 PM
Sounds like Balsam Fir (Abies balsamea) a resinous conifer.
But maybe Balsam Poplar (Populus balsamifera) which is also common in Canada and interior Alaska. Coastal areas have Black Cottonwood which is indistinguishable to me from Balsam Poplar. This group of broadleafs drips a nasty resin on cars that turns blackish known as Balm of Gilead.

Bill Bohan
01-17-2013, 02:12 PM
The hue of green in gold may be a result of a small percentage of the element Cadmium.