Mining for 'free' gold is called alluvial mining
. Both government authorities and small-scale miners agree that alluvial mining
is the most destructive to the environment.
Meanwhile, these are people who have installed heavy machines (changfan) on water bodies and seriously doing alluvial mining
without any regulation.
Exumax is a private Colombian based alluvial mining
company which, since September 2016, has been progressing the company's exploration and development programme on its near surface platinum and gold assets located in the Choco Region of Colombia.
As a consequence of these interventions, it was compulsory that the government control alluvial mining
through increased monitoring.
Alluvial gold has been recovered in numerous historic dredging operations on A-16 and active alluvial mining
is being conducted very near the area being Trado sampled by GMV geologists.
This survey will cover a 34 km2 area upstream from the alluvial mining
Further investigation of artisanal alluvial mining
as a risk factor for Buruli ulcer is recommended.
The Diamond Development Initiative found that "alluvial mining
areas are more vulnerable than others to infectious diseases.
Types of metal mining include placer or alluvial mining
and lode or hardrock mining.
Presently Venezuela, Guyana, Indonesia, Liberia, Ivory Coast, Lesotho and Swaziland all produce some diamonds; and alluvial mining
in the northwestern part of Hunan Province, China has recently yielded a beautiful 1.2-cm macle twin which appeared in Tucson around ten years ago (Moore, 1993).