San Diego’s Hidden Treasure: Exploring Eagle Mine in Julian

One word sums up California in the last half of the 19th century – gold. As in, there’s gold in them thar hills.

The 1848 discovery of gold in the South Fork American River ignited the greatest adventure of the age: the California Gold Rush. As fortune-seekers flooded the Sierra Nevada foothills, a different kind of prospecting was taking shape in the Cuyamaca Mountains of Southern California.

It’s that SoCal mining history that we set out to explore when some friends visited us from Japan over the winter holidays. We met them in the historic mining town of Julian to take the Eagle Mine Tour of one the major early gold mining claims in Southern California’s Cuyamaca Mountains.

Eagle Mine Tour Overview

Located an hour and a half from our home in San Diego, Julian is best known for apples – apple pies, apple cider, apple shirts, apple trinkets, you name it. We often stop here for lunch on our way further east to Anza-Borrego Desert State. Julian gets crowded on fall and winter weekends and holidays, and that turned out to be the case on this visit.

After grabbing some pizza, BBQ, and beer at Julian Beer Company, we headed to Eagle Mine, which is located less than half a mile from Main Street and an easy walk from town. Before the mine tour, we panned for gold dust and visited the gift shop, which sells minerals, rocks and gems, in addition to other items.

Julian’s Gold Mining History

Julian’s gold prospecting history took off in 1870, when a man named H.C. Bickers was following bear tracks up a ravine near Julian and he discovered quartz rocks that contained gold.

The next day was George Washington’s birthday, and Bickers and his partners named the claim the Washington Mine in honor of the first president’s birthday.

While prospectors had panned small amounts of gold from local creeks, the mine was the first real gold strike in the Julian and the first of several mines that would be established during the period.

Unlike Northern California, where gold was found in nuggets, Julian’s gold was locked in underground veins of quartz. This required miners to remove the ore (rock) from the mine and then crush and process the rocks to extract the gold, backbreaking and toxic work that produced an ounce or two of gold on a good day.

Eagle Mine also started in 1870 and was next to High Peak Mine, a separate claim. The two are now connected through a labyrinth of tunnels deep underground. The mine was operational until 1937 and generated around $100,000 worth of gold during that time.

After being abandoned for many years, it was purchased in 1967 by Ed and Ellen Sprague, whose grandson is the current owner of the mine and tour operation. 

In the mine’s heyday, miners spent countless hours chiseling through rock with picks and shovels or blasting out sections of rock with dynamite, their candle lanterns casting the only light in the enveloping darkness.

Our guide told us the miners made around a dollar a day and had a short life expectancy. While only two deaths from a shaft collapse were recorded during its year of operation, no doubt many injuries went unreported in those more rugged times.

The tour brought us through two levels of the mine, and the guide did a nice job of explaining the geological history that deposited veins of gold-lined quartz in the mountains. Eagle Mine goes deep into the earth, below the level where the tour explores. The mine has 4000 feet of tunnels on 11 levels, some of which are over 400 feet under the surface.

Under Pressure

The presence of gold-bearing quartz veins in this area is a story millions of years in the making, a tale of immense heat, pressure, and fluid dynamics deep within the Earth’s crust.

The journey begins with the Earth’s tectonic activity. Millions of years ago, the movement of tectonic plates created immense pressure and heat, leading to the formation of magma deep within the Earth. This magma, rich in various minerals and fluids, began its ascent towards the Earth’s surface, carving its path through the surrounding rock.

As this hot, mineral-laden fluid made its way upwards, it encountered cooler temperatures, causing the minerals to crystallize and form veins. Among these minerals was quartz, a common vein-filling mineral due to its high melting point and resistance to chemical weathering.

The unique conditions of high temperature and pressure, combined with the presence of certain elements like silicon and oxygen, were perfect for the formation of these quartz veins.

But the story doesn’t end there. The same hydrothermal fluids that carried the quartz also contained dissolved gold. As the fluids cooled and solidified to form quartz, the gold, unable to remain in solution, precipitated out, depositing itself within the quartz veins.

Over millions of years, these gold-bearing quartz veins grew in size, eventually becoming the rich deposits that attracted miners to places like Eagle Mine.

Today, these quartz veins, visible as white or light-colored streaks running through the darker host rock, are not just a source of gold. They are also a geological diary, recording the incredible forces and processes that shaped our planet, offering us a glimpse into the dynamic and ever-changing world beneath our feet.

Tough Way to Make a Living

At one point, the guide blew out the candle the foreman used to keep his books to demonstrate what it was like to be deep underground without a trace of sunlight. He said miners would often navigate the tunnels without light to save money on candles. 

After exiting the mine, the guide brought us to the stamp mill, the machine where the quartz ore was crushed into dust so the gold could be extracted. 

What struck me was that it must have been a challenging life and to wonder what led people to take up such a difficult way to make a living – either through choice or necessity. 

Eagle Mining Co. keeps the rich mining history of San Diego’s mountains alive, and I highly recommend a visit.