Largest Lithium Deposit in the World Found in the USA

McDermitt Caldera Could Be Home to World's Largest Lithium Deposit

A team of scientists has discovered what could be the largest lithium deposit in the world, located in the McDermitt Caldera on the border of Nevada and Oregon. The caldera is a large, collapsed volcanic crater that is thought to have formed about 19 million years ago.

A recent study by a team of volcanologists and geologists suggests that the McDermitt Caldera, located on the Nevada/Oregon border, may contain some of the largest deposits of lithium on Earth. The researchers, from Lithium Americas Corporation, GNS Science, and Oregon State University, studied parts of the caldera and developed a theory to explain the abundance of lithium in the area.

Over the past few decades, lithium has become a highly valued soft metal, due primarily to its use in a wide variety of battery types. Because its value has continued to increase, scientists working for mining companies such as Lithium Americas Corporation have been looking for sources.
  

A map of the McDermitt Caldera on the Oregon-Nevada border. MacGregor Campbell / OPB

The McDermitt Caldera is approximately 45 kilometers long and 35 kilometers wide. Prior research has suggested it formed as part of the Yellowstone hotspot, which led to the formation of a sequence of calderas. Its origin dates to approximately 19 million years ago.

In 2017, another team of researchers found evidence that one part of the caldera called Thacker Pass could be among the largest sources of lithium ever found. Lithium Americas obtained a stake at the site and began testing mining operations. Soon thereafter, they ran into opposition from locals and Native American groups, but eventually won the right to mine at the site.

Since that time, the research team has been collecting and analyzing samples, looking for the best place to begin major mining operations. But to find it, they and many other experts in the field believe they must find an explanation for how the lithium got there in the first place. In their paper, the researchers suggest a theory—one Lithium Americas plans to use to begin its mining operations.

Their theory posits that after a volcano erupted (creating among other things, lithium), a hydrothermal enrichment occurred—magma deep unground pushed its way to the center of what is now the caldera, leading to the formation of the Montana Mountains. As that happened, faults, fissures and fractures were created, allowing lithium to seep up toward the surface. This process also transformed much of the smectite into illite (different forms of lithium), which wound up along the southern rim of the basin. That, they conclude, explains why lithium is so abundant there.
 

Lithium mineralization in McDermitt caldera. (A) Simplified map of McDermitt Caldera, locations of active and historic mining projects, locations of drillholes colored according to maximum downhole Li assay value, and locations of drillhole samples used in this study.

The scientists are still working to understand how the lithium deposits formed and how they can be best extracted. However, the discovery is a significant step forward in the search for new sources of lithium.

The discovery of this large lithium deposit has been met with mixed reactions. Some people are excited about the potential economic benefits that it could bring to the region. Others are concerned about the environmental impacts of mining, such as water pollution and the destruction of habitat.

The scientists involved in the discovery have said that they are committed to mining the lithium in a sustainable way. They have also said that they will work with local communities to address any environmental concerns.

The discovery of the lithium deposits in the McDermitt Caldera is a significant event. It could help to meet the growing demand for lithium and play a role in the development of clean energy technologies. However, it is important to carefully consider the environmental impacts of mining before any development takes place. 

The above story is based on Materials provided by Columbia University.