From Mine to Market
Here's how gold from the Nigerian state Zamfara reaches the worldwide market.
- Ore is collected from mines near Sunke.
- The ore is bagged and brought by motorcycle to villages like Dareta or Sunke, where villagers grind the ore and then wash the mix over a ridged board. Villagers who do the processing themselves then use mercury to extract the gold.
- The result is then sold to gold traders in Gusau, the capital of Zamfara, where remaining dirt and impurities are separated.
- The gold is driven to the Benin border and turned over to dealers from the port city of Cotonou.
- The dealers then sell this gold to wholesalers from Europe and the Middle East, who in turn introduce that gold to the worldwide market.
Read more about how artisanally mined gold from Nigeria reaches the world market
Source: Bloomberg Reporting
The Toxins of Mining
Toxic materials are used in both industrial and small-scale mining to extract gold from ore and rock.
Gold mines typically do not contain lead, but ore from lead-filled mines in northern Nigeria created a lead-poisoning crisis in villages there, where at least 284 children died. According to the CDC, exposure to lead can cause learning disabilities, behavioral problems, and mental retardation at low levels. Increased exposure can cause seizures and comas, if not death.
Sodium cyanide is used in industrial mining to leech gold out of mined rocks. The CDC says short-term effects of cyanide exposure can include rapid breathing, restlessness, dizziness, weakness, headache, rapid heart rate, nausea and vomiting. Long-term exposure can result in convulsions, low blood pressure, slow heart rate, loss of consciousness, lung injury, and respiratory failure leading to death.
In small-scale mining, mercury is used to separate gold from crushed rock. Short-term exposure to high levels of mercury vapors may cause respiratory failure, nausea, vomiting, diarrhea, increases in blood pressure or heart rate, skin rashes, eye irritation, and kidney damage.
Small-Scale Mining, Large-Scale Pollution
When small scale miners in northern Nigeria ground ore from local gold mines filled with lead, they spewed lead dust across the ground where their children played and poultry grazed.
A typical 50kg bag of ore from Zamfara, Nigeria, yields 0 to 3 grams of gold. That amounts to a gold coin no larger than half of a U.S. dime.
The lead content of rock from some mines in Nigeria is so large that for every dime-sized amount of gold collected, a softball sized amount of lead must also removed.
Earth tested in one village in Nigeria had lead levels of 50,000 parts per million or ppm. The EPA limit for areas around playgrounds is 400 ppm.
Source: Bloomberg Calculations
Read more about the effect lead from gold mining is having on villages in Nigeria
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