What’s The Largest County In Texas And What Makes It Unique?

Written by Nilani Thiyagarajah
Updated: March 2, 2023
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Key Points

  • Texas is the largest state in the continental United States.
  • The largest county in Texas, when looking at land area, is Brewster County.
  • Brewster County is located in the Trans-Pecos region of western Texas. It’s home to Big Bend National Park, which is the biggest park in the state of Texas.

There are so many things about the land that we cannot necessarily see with a cursory glance. However, sometimes, if you do some digging, you can find different types of treasure.

Texas is the largest state in the continental United States. If you look at all of the land in this huge state, you’re bound to find something valuable.

But there’s so much to look at in the state of Texas. After all, we’re looking at 268,597 square miles of land! We might want to start by looking at just one county. So, what’s the largest county in Texas, and what makes it unique?

The Largest County In Texas

The largest county in Texas, by land area, is Brewster County; it is 6,192 square miles.


The largest county in Texas, when looking at land area, is Brewster County. It contains 6,192 square miles (16,040 square kilometers) of land, which makes it bigger than Connecticut by more than 500 square miles and more than three times the size of Delaware!

Brewster County is located in the Trans-Pecos region of western Texas. It’s home to Big Bend National Park, which is the biggest park in the state of Texas. Surrounding counties include Presidio, Jeff Davis, Pecos, and Terrell. The Rio Grande borders Brewster County on its southern side.

Nature In Brewster County In Texas

There are many plants and animals native to Brewster County. This area has a variety of elevations that range between 1,700 and 7,825 feet above sea level. It’s fairly rocky and mountainous terrain. Most of this land drains into the Rio Grande, although the northern portion drains more into the Pecos River.

At lower elevations, there is relatively drought-resistant vegetation, such as desert shrubs, cacti, and sparse grasses. In somewhat higher elevations, there are vast grasslands, as well as several trees, including the juniper, white oak, Douglas fir, maple, and Arizona pine.

Several mammals have made this area their home, including the white-tailed deer, pronghorn antelope, bobcat, desert bighorn sheep, coyote, black bear, and prairie dog. There are also many birds, including the white-winged dove, roadrunner, golden eagle, and quail. Of course, this is far from being an exhaustive list, as many more animals live here.

What Makes Brewster County In Texas Unique?

Brewster County is unique because of its history of mercury production.

©Silvio Ligutti/Shutterstock.com

The land of Brewster County is unique because of the quantities of ore that people can use to produce mercury. All of the mercury mining in the state of Texas has taken place in Brewster and Presidio Counties. The area of production is known as the Terlingua District. This is the third-largest mercury-producing region in the United States.

In 1884, Ignatz Kleinman, a merchant of Presidio, made the first important discovery of mercury in the area. This started a mining boom that made this region one of the most important sources of mercury in the United States for the first half of the 20th century. The first flask of mercury (weighing 76 pounds) was made in 1886.

The development of mercury mining, as well as other industries that use the natural resources of the land, led to a population boom of over 700% between 1890 and 1910. Southern Brewster County turned into a significant source of wealth for northern rail towns; they would ship mercury and other natural resources north in exchange for other products.

Mercury mining became less prominent in the 1940s when the Mariscal Mine and Chisos Mine ran out of ore. However, a new ore body was discovered at Buena Suerte. This extended the Terlingua District several miles to the west.

When prices of mercury were high, the Brewster County economy tended to be much stronger. However, demand for mercury decreased in the 1970s. As a result, the mines were shut down for the final time. There were no reports of further production after 1973.

How Is Mercury Mined?

Extracting mercury from the earth can be somewhat challenging, particularly when you consider that mercury exists in liquid form at room temperature.

The majority of mercury that forms in the ground forms within a sulfide ore that miners refer to as cinnabar (as was the case in Brewster County). A common way for them to separate the mercury from the cinnabar is to crush the entire ore and then heat the ore in a furnace in order to cause the mercury to vaporize.

Once they have obtained the mercury vapor, they can condense it into its normal liquid form.

Alternatively, they can use the process of hydrometallurgy, which involves leaching away the cinnabar and treating the concentrated mercury with sodium sulfide and sodium hydroxide solutions. Then, they can use aluminum or the process of electrolysis to precipitate the mercury. However, this method is less common, as the leaching process can be quite expensive.

Uses For Mercury Mining

The U.S. has cut down on the mining and use of mercury, as mercury deposits and emissions can present a biological and ecological hazard.


Mercury has the popular nickname of “quicksilver” because it is silver, in addition to being the only metal that is liquid at ambient pressure at room temperature.

In the past, mercury has been used in the synthesis of many products. In the mid-1800s, for example, industrial workers would use it to make hats during the felting process. Because mercury is a good conductor of electricity, industries still use it in products such as batteries and switches.

Currently, developing countries still use mercury for industrial processes, such as the production of PVC pipes. Miners also use mercury to extract gold, even though this practice is illegal in most locations.

The use and release of mercury is a cause for environmental concern, as mercury emissions negatively affect air quality.

Additionally, when elemental mercury ends up being deposited into bodies of water, microscopic organisms convert it into methylmercury. Fish and shellfish often eat this byproduct, and humans who consume these animals can end up dealing with potentially hazardous mercury exposure.

The mining of mercury as a primary mineral commodity in the United States stopped in the early 1990s. The United States has significantly cut down on atmospheric emissions of mercury. The country has also made nearly a 90% reduction when it comes to mercury use in products.

Any mercury sourced from the United States now comes from environmentally preferable sources, such as recycled mercury and mercury that has been obtained as a byproduct of extraction.

The photo featured at the top of this post is © Steve Price/Shutterstock.com

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