Frequently Asked Questions

Q. What is cyanide?

A. Cyanide refers to a group of compounds made of carbon and nitrogen. Cyanide solutions readily bond with gold, silver and other metals, which is why the mining industry uses it. Cyanide is usually stored and transported as a solid. It is stable when dry. Most cyanide solids will dissolve in water to produce toxic cyanide gas. Cyanide gas is colorless and smells like bitter almonds. Cyanide is produced naturally in minute, harmless quantities in several plants, such as in apple seeds, apricot pits, soil bacteria and species of invertebrate organisms.

Q. How does cyanide affect living organisms?

A. Cyanide is highly toxic. Cyanide is the killing agent used in gas chambers. Cyanide poisoning can occur through inhalation, ingestion, and skin or eye contact. One teaspoon of a 2% solution can kill a person. In general, fish and other aquatic life are killed by cyanide concentrations in the microgram per liter (part per billion) range, whereas bird and mammal deaths result from cyanide concentrations in the milligram per liter (part per million) range. A cyanide spill in Romania on January 30th, 2000, killed thousands of tons of fish and made a significant portion of the Tisza River watershed undrinkable and hostile to aquatic life. Evidence shows that cyanide compounds linger in affected plant and fish tissues and can persist in the environment for long periods of time.

Q. How is cyanide used in mining?

A. Cyanide-leaching allows mining companies to reopen and expand mines containing what were previously unprofitable mineral reserves. There are two types of cyanide-leaching processes used by the modern mining industry. Vat-leaching, where extracted ore is combined with cyanide in vats, and heap-leaching, which involves:

• Digging enormous pits (often larger than some cities) and piling the extracted ore into heaps that would cover many football fields several hundred feet high;
• Spraying a cyanide solution over the heaps so that the cyanide trickles down through the ore, bonding with microscopic flecks of gold or silver, whereupon a heap pad (a rubber blanket), underlying the heap, channels the solution into a holding pond; and,
• Stripping the solution of the precious minerals, recovering the used cyanide, then respraying the cyanide solution over the heap.

In the extraction of copper, nickel, cobalt and molybdenum, cyanide is used during the milling and concentration processes.

Q. What are the dangers of using cyanide?

A. Cyanide reacts with many other elements and is known to breakdown into several hundred different cyanide-related compounds. Despite the risks posed by these breakdown compounds, mines are not required to monitor or report these chemicals.

Cyanide-leaching, as practiced by the modern mining industry, is inherently dangerous to the environment and the communities surrounding a mine that uses the process. As cyanide use continues, so do serious accidents and spills. Four recent examples are:

• Zortman-Landusky Mine, Montana, 1982: Fifty-two thousand gallons of cyanide solution poison the drainage that supplies fresh drinking water for the town of Zortman. A mine employee discovered the accident when he noticed the smell of cyanide in his tap water at home.
• Summitville Mine, Colorado, 1992: Summitville gold mine was responsible for contaminating 17 miles of the Alamosa River with cyanide and other contaminants.
• Kumtor Gold Mine, Kyrgyzstan, central Asia, 1998: A truck carrying 2 tons of sodium cyanide crashed into the Barskoon River. Two thousand six hundred poison cases and 4 deaths were reported in the aftermath.
• Aural Gold Plant, Romania, Eastern Europe, 2000: A cyanide-laden tailings spill sent a toxic slug of cyanide and metals rolling down the Tisza River and into the Danube, killing aquatic wildlife and poisoning water supplies as far as 250 miles downriver.

Q. Does society require we use cyanide to supply gold?

A. Probably not. Potential cyanide-mining substitutes aside, we may not need to use cyanide in gold mining simply because there are already enormous supplies of gold, already mined and refined, above ground in reserve banks (like the Federal Reserve in the U.S.). Reserve banks and international financial institutions store more than 34,000 tons of gold as currency reserves, an amount equivalent to nearly one-quarter of all gold ever mined. A dollar used to be redeemable for a dollar’s worth of gold. That is no longer the case now; gold reserves are an anachronism of a past era. Meanwhile, 34,000 tons of gold could satisfy current global demand for 8 years. (85% of the gold demand is for jewelry, only 12% for industry.) Moreover, by holding these gold reserves, central banks are costing taxpayers money. The U.S., the world’s largest holder of gold reserves, has lost $215 billion since 1980 due to plummeting gold prices, and we stand to lose more if other governments sell their gold reserves first, which is already happening. Reserve banks in the Netherlands, Switzerland, the UK, and Australia have already sold or decided to sell significant portions of their gold reserves.

Q. Is cyanide safe, and is it necessary?

A. Despite mining industry assertions to the contrary, the record clearly demonstrates that cyanide leach mining is not being practiced safely. It is potentially very dangerous to the environment, wildlife, and humans. The hardrock mining industry has a history of cyanide spills, with billions of gallons of cyanide contamination released into the environment, ever since cyanide-leaching began in the 1970s. Furthermore, cyanide-mining may not be necessary. Enormous stockpiles of unused gold already exist above ground in reserve banks around the world.

Q. Are there alternatives to cyanide?

A. The U.S. Environmental Protection Agency lists several alternatives to cyanide, including starch and sulfur dioxide. In 1999, 16 of 18 leading U.S. zinc mines and 11 of 15 leading U.S. copper mines did not use cyanide.

For gold and silver extraction, the Haber Gold Process (HGP) has been proposed as a possible alternative. HGP has undergone preliminary and follow-up testing by mining engineering groups, which have concluded that HGP results in more gold recovery over a shorter period of time than the cyanide-leaching processes, with a cost comparable to, or less than, cyanide-leaching. In addition, HGP passed the California Department of Health Services Acute Aquatic Toxicity Bioassay test, which tests the toxicity of a substance on wildlife. These claims are made by the Haber Inc. web site and, although independent testing of HGP has been done, there are no public documents that can verify these claims.

In addition, the cyanide-free biocatalyzed leaching process from YES Technologies uses a bisufide-leaching agent which is 200 times less toxic than cyanide. Preliminary test results indicate chemical reagent costs associated with this process could be 80% lower than cyanide.