Gold Science

Toxic waste is a devastating consequence of dirty gold mining practices. Cyanide heap leaching is the cheapest way to extract gold and as a result, is commonly used around the world. The process leaves behind mounds of wasted rock and leaking toxic materials. And because leaching is a time consuming process that takes months, contamination of the surrounding environment with cyanide is nearly impossible to control. Accidents involving cyanide have made the practice of heap leaching even more toxic. The United Nations Environment Program reports that more than a dozen reservoirs containing cyanide-laden mine waste collapsed from 1985 to 2000. This has led to devastating consequences in Romania, Ghana, Peru, Costa Rica, and other countries scattered around the world.. Cyanide is a rapidly acting and deadly chemical. Exposure to high levels of cyanide harms the brain and heart, and may cause coma and death. Exposure to lower levels may result in breathing difficulties, heart pains, vomiting, blood changes, headaches, and enlargement of the thyroid gland. Disastrous spills have forced the gold industry to change how it handles cyanide by setting new standards for transporting and storing the chemical. New industry bodies have called on companies to submit to inspections. But the cyanide code is voluntary and not enforced by governments. And cyanide is not the only toxic waste associated with gold mining: when the rock disturbed by mines is exposed to rain and air for the first time, the newly exposed rock can contain sulfides that will react with oxygen to make sulfuric acid. This sulfuric acid also frees heavy metals like cadmium, lead and mercury, which are harmful to people and fish even at low concentrations.

First of all, gold mines release highly toxic substances that pollutes the water. Gold mines dispose of highly toxic substances in nearby water resources. These toxic substances cause crucial effects on these water resources. An article named Poisoned Waters from the website No Dirty Gold stated “Long term effects include acid mine drainage, which raises acid levels in rivers and Lakes ( harmful to wildlife and people),”. Cyanide heap leaching is the most common technique of gold mining, but by using that technique gold mines release cyanide. Cyanide is a highly toxic material and it poisons and pollutes the water. Secondly, gold mining causes air pollution. Gold mines produces a lot of dust and toxic materials that pollutes the air. Borkowski states that the toxic substances which are contained in the waste that the gold mine produce could pollute the air, soil and water (2003). And also according to the article Polluted Air, dust and exhaust fumes and the pollution caused by them...

Case Study 1: Gold a) Gold is used as a conductor in electronic devices. It is a very good conductor for fast, small currents. b) Dentists use gold for fillings. It is easier to use and doesn’t leave rust marks on your teeth. c) Used in crowns for royalty. It shows a sign of importance. d) It is used in the making of glass, it helps with climate and temperature control in the room.

Case Study 2: Gold a) Gold mining releases a toxic fluid called cyanide, which is extremely dangerous if ingested. b) The machines used for gold mining release fumes and exhaust into the air which can cause long term problems and diseases. c) People living near gold mines have a high risk of being infected by the cyanide in the water if they drink it. They also have a high risk of getting diseases, such as lung cancer, from the pollutants in the air.

Write-up Aim: To determine the process whereby gold is extracted. Apparatus:    

beaker test tubes glass rod dropper

Observations: In the first solution, the copper separated to the top of the beaker and the sand went to the bottom. The ammonia solution and the hydrogen peroxide solution separated from the sand. The mixture turned blue. In the second part of the investigation, the zinc turned black after being placed in the blue decanted solution.

Conclusion: Zinc turns black when it enters a solution of ammonia and hydrogen peroxide.