Midas and the River Pactolus

The myth of King Midas and his golden touch has been told and retold as a fairy tale for centuries on end. However, it is not commonly known that this tale is really this etiological myth, i.e. a myth that explains a real-world phenomenon. In this case, they say the actions of King Midas account for the rich alluvial deposits of the Pactolus river.

According to the myth, King Midas earned the gratitude of Dionysus, Greek god of winemaking and revelry, for hosting the god’s mentor. As thanks, Dionysus agreed to grant Midas any wish he desired. Midas wished that whatever he touched would turn to gold. However, he soon realized his blessing was a curse when the food he tried to eat turned to gold and hugging his daughter resulted in the same.

Saddened and starving, Midas prayed to Dionysus to remove his golden touch. Dionysus answered and said that if Midas would wash his body in the river Pactolus, he would wash away his curse. When Midas did this, his powers washed away from him into the river.

The Pactolus was known for its rich deposits of electrum. The river was so rich in fact, that the ancient state of Lydia based its economy on it. In addition, the Lydians are credited with inventing the first gold coins in or around 7th century BCE. All thanks (mythically) to King Midas.

The Legend of El Dorado

The legend of El Dorado has been around for hundreds of years. However, not many people are familiar with its intricacies. As a matter of fact, El Dorado, translated from Spanish as “the golden one” originally referred to a person.

As the Spanish explored the New World during the 16th century, they came across a tribe in the Columbian highlands, known as the Muisca. The tribe was rich in terms of both culture and wealth. However, of particular interest was their elaborate initiation ceremony for new tribal chiefs. After a short ritual seclusion, the chief-to-be travelled with his people to Lake Guatavita to make a sacrifice to their god. Once at the lake, they would build a raft and lavishly decorate it. The chief-to-be would board the raft, where he was then coated from head to toe in gold dust – becoming El Dorado. He also brought with him on the raft a pile of gold and gems. After being covered in gold, he would push this pile into the lake as a sacrifice and the ritual would be complete – cementing him as the new tribal chief.

Of course, such a tribe with gold to spare was quickly overrun with conquistadores. Gold was religiously significant to the Muisca, and one of their legends was based on an entire city made of gold, also called El Dorado. The conquistadores heard the tale from tribesmen they had captured, and so set off on a number of unsuccessful expeditions to find the mythical city.

Gold Mining and Cyanide

When you think of gold mining, you probably think of an old prospector searching for nuggets in the hillside. Or, if you are more industrial minded, you imagine a network of sluices capturing a bounty of alluvial gold. While such mining forms are not extinct, they are a bit antiquated. Gold is extremely valuable, so miners want to get every molecule they can. Using modern mining techniques, they literally can get every molecule of gold out of a chunk of ore. Chemical mining is one of the most efficient ways to mine gold and one of the most popular. It’s also one of the most dangerous, as it uses cyanide.

Gold cyanidation technically started back in 1783 when Carl Wilhelm Scheele discovered that one could dissolve gold in an aqueous cyanide solution. In 1887, this knowledge was applied to gold mining with the development of the MacArthur-Forrest Process. The basic premise of this process is simple: gold ore is crushed and ground as fine as possible, then combined with a solution of cyanide which leaches the gold out of the ore. Later iterations of the MacArthur-Forrest Process oxygenated the cyanide mixture to increase the rate at which cyanide leached gold from the solution. Once the gold is successfully leached from the ore, miners have a number of options to recover the gold from the cyanide solution, including the carbon-in-pulp method, the Merrill-Crowe process, electrowinning, and the Resin-in-pulp method.

Despite it effectiveness, gold cyanidation has come under fire from time to time because of the danger of using so much cyanide in major mining operations. Spills or leaks in the system can – and have – caused major environmental damage. Fortunately, cyanide solutions break down rapidly in natural conditions. So, if a disaster occurs, it tends to be short lived. As long as safe practices are enforced, gold cyanidation is an efficient method for mining gold.