The Real Golden State: Gold Production in Nevada

Thanks to the world famous silver discoveries of the 19th century that unveiled Nevada’s precious metal potential, the state today is known by many as “The Silver State”.

However, it’s possible that nickname may need to be updated. In the last few decades, Nevada has become a prolific gold producer, accounting for 84% of total U.S. gold production each year.

Today’s infographic from Corvus Gold showcases why Nevada may have a better case for deserving California’s nickname of the “Golden State”: we look at the state’s gold production, exploration potential, and even its rich history.

A Defining Era for the American West

The discovery of the Comstock silver lode in 1859 sparked a silver rush of prospectors to Nevada, scrambling to stake their claims. News of the discovery spread quickly throughout the United States, drawing thousands into Nevada for one of the largest rushes since the California Gold Rush in 1849. Mining camps soon thrived and eventually became towns, a catalyst that helped turn the territory into an official state by 1864.

Interestingly, many of the early mines also produced considerable quantities of gold, indicating there was more to the state than just silver.

1. The Comstock Lode: 8,600,000 troy ounces (270t) of gold until 1959
2. The Eureka district: 1,200,000 troy ounces (37t) of gold
3. The Robinson copper mine: 2,700,000 troy ounces (84t) of gold

The Comstock Lode is notable not just for the immense fortunes it generated but also the large role those fortunes had in the growth of Nevada and San Francisco.

In fact, there was so much gold and silver flowing into San Francisco, the U.S. Mint opened a branch in the city to safely store it all. Within the first year of its operation, the San Francisco Mint turned $4 million of gold bullion into coins for circulation.

While California gold rushes became history, Nevada mining was just beginning and would spur the development of modern industry. In 2018, California produced 140,000 troy ounces of gold, just a fraction of the 5.58 million oz coming out of Nevada’s ground.

Nevada Gold Mining Geology: Following the Trends

There are three key geological trends from where the majority of Nevada’s gold comes from.

1. Cortez Trend
2. Carlin Trend
3. Walker Lane Trend

Together these trends contributed nearly 170 million ounces of gold produced in Nevada between 1835 and 2018, making it the United States’ most productive gold jurisdiction, if not the world’s.

The bulk of production comes from the Cortez and Carlin Trends, where mines extract low grade gold from a particular type of mineral deposit, the Carlin Type Gold deposit. It was the discovery and technology used for processing these “invisible” deposits that would turn Nevada into the golden powerhouse of production.

Today, the world’s largest gold mining complex, Nevada Gold Mines, is located on the Carlin Trend. The joint venture between Barrick and Newmont comprises eight mines, along with their infrastructure and processing facilities.

Despite the prolific production of modern mines in the state, more discoveries will be needed to feed this production pipeline—and discoveries are on the decline in Nevada.

Looking to the Future Through the Past: The Walker Lane Trend

The future for gold mining in Nevada may lie in the Walker Lane Trend. This trend is host to some of the most recent gold discoveries, and has attracted the interest of major mining companies looking to conduct exploration, and eventually, production.

Walker Lane stands out with exceptional high-grades, growing reserves, and massive discovery potential. It also played an integral role in the history of the state beginning with the 1859 discovery of the Comstock Lode, and it seems likely to continue doing so in the future.

Mapped: The Geology of the Moon in Astronomical Detail

If you were to land on the Moon, where would you go?

Today’s post is the incredible Unified Geologic Map of the Moon from the USGS, which combines information from six regional lunar maps created during the Apollo era, as well as recent spacecraft observations.

Feet on the Ground, Head in the Sky

Since the beginning of humankind, the Moon has captured our collective imagination. It is one of the few celestial bodies visible to the naked eye from Earth. Over time different cultures wrapped the Moon in their own myths. To the Egyptians it was the god Thoth, to the Greeks, the goddess Artemis, and to the Hindus, Chandra.

Thoth was portrayed as a wise counselor who solved disputes and invented writing and the 365-day calendar. A headdress with a lunar disk sitting atop a crescent moon denoted Thoth as the arbiter of times and seasons.

Artemis was the twin sister of the sun god Apollo, and in Greek mythology she presided over childbirth, fertility, and the hunt. Just like her brother that illuminated the day, she was referred to as the torch bringer during the dark of night.

Chandra means the “Moon” in Sanskrit, Hindi, and other Indian languages. According to one Hindu legend, Ganesha—an elephant-headed deity—was returning home on a full moon night after a feast. On the journey, a snake crossed his pathway, frightening his horse. An overstuffed Ganesha fell to the ground on his stomach, vomiting out his dinner. On observing this, Chandra laughed, causing Ganesha to lose his temper. He broke off one of his tusks and hurled it toward the Moon, cursing him so that he would never be whole again. This legend describes the Moon’s waxing and waning including the big crater on the Moon, visible from Earth.

Such lunar myths have waned as technology has evolved, removing the mystery of the Moon but also opening up scientific debate.

Celestial Evolution: Two Theories

The pot marks on the Moon can be easily seen from the Earth’s surface with the naked eye, and it has led to numerous theories as to the history of the Moon. Recent scientific study brings forward two primary ideas.

One opinion of those who have studied the Moon is that it was once a liquid mass, and that its craters represent widespread and prolonged volcanic activity, when the gases and lava of the heated interior exploded to the surface.

However, there is another explanation for these lunar craters. According to G. K. Gilbert, of the USGS, the Moon was formed by the joining of a ring of meteorites which once encircled the Earth, and after the formation of the lunar sphere, the impact of meteors produced “craters” instead of arising from volcanic activity.

Either way, mapping the current contours of the lunar landscape will guide future human missions to the Moon by revealing regions that may be rich in useful resources or areas that need more detailed mapping to land a spacecraft safely .

Lay of the Land: Reading the Contours of the Moon

This map is a 1:5,000,000-scale geologic map built from six separate digital maps. The goal was to create a resource for science research and analysis to support future geologic mapping efforts.

Mapping purposes divide the Moon into the near side and far side. The far side of the Moon is the side that always faces away from the Earth, while the near side faces towards the Earth.

The most visible topographic feature is the giant far side South Pole-Aitken basin, which possesses the lowest elevations of the Moon. The highest elevations are found just to the northeast of this basin. Other large impact basins, such as the Maria Imbrium, Serenitatis, Crisium, Smythii, and Orientale, also have low elevations and elevated rims.

The colors on the map help to define regional features while also highlighting consistent patterns across the lunar surface. Each one of these regions hosts the potential for resources.

Lunar Resources

Only further study will resolve the evolution of the Moon, but it is clear that there are resources earthlings can exploit. Hydrogen, oxygen, silicon, iron, magnesium, calcium, aluminum, manganese, and titanium are some of the metals and minerals on the Moon.

Interestingly, oxygen is the most abundant element on the Moon. It’s a primary component found in rocks, and this oxygen can be converted to a breathable gas with current technology. A more practical question would be how to best power this process.

Lunar soil is the easiest to mine, it can provide protection from radiation and meteoroids as material for construction. Ice can provide water for radiation shielding, life support, oxygen, and rocket propellant feed stock. Compounds from permanently shadowed craters could provide methane, ammonia, carbon dioxide, and carbon monoxide.

This is just the beginning—as more missions are sent to the Moon, there is more to discover.

Space Faring Humans

NASA plans to land astronauts—one female, one male—to the Moon by 2024 as part of the Artemis 3 mission, and after that, about once each year. It’s the beginning of an unfulfilled promise to make humans a space-faring civilization.

The Moon is just the beginning…the skills learned to map Near-Earth Objects will be the foundation for further exploration and discovery of the universe.