Hidden underneath Utah’s West Desert are promising deposits of a critical mineral you have probably never heard of, but you are holding it in your hand right now if you are reading this story on a smartphone.
Indium is produced nowhere in the United States, yet it is essential for touch screens and display panels that are ubiquitous in modern society.
Hoping to cultivate domestic supplies, the federal government has awarded the Utah Geological Survey a $300,000 grant to evaluate deposits of indium-bearing minerals in western Juab County over the next three years. Drilling cores recovered here have documented high concentrations of sphalerite, a mineral rich in indium, copper and zinc, according to UGS senior scientist Stephanie Mills.
“We’re going to be researching the science of why is there so much indium here,” said Mills, the principal investigator on the study, “how is it hosted in the deposit and is there anything we can learn from this that would help us find similar deposits in the future.”
The U.S. Geological Survey (USGS) has designated indium a strategically important mineral because of its importance to the aerospace, defense, energy and telecommunications sectors. A soft silver-white metal, indium (symbol In) is 49th on the Periodic Table, sitting between cadmium and tin.
U.S. industry relies entirely on foreign sources of indium, with most it coming from China, Canada, South Korea and France, according to the USGS. American manufacturers bought 187 short tons last year, worth $37 million. That translates to nearly $100 a pound, and prices are expected to climb with growing demand.
World production was 1,012 tons last year with China accounting for 58%.
According to Mills, Utah harbors deposits of 38 minerals appearing on the USGS’s official list of 50 critical minerals, such as lithium used in advanced battery technology and bismuth needed in medical research.
Three major geologic terrains come together in the Beehive State, resulting in a large variety of mineral deposits, Mills said. Utah’s share of the Rocky Mountain region is loaded with precious metals that drove the mining booms of the 19th century, while the Colorado Plateau is rich in the uranium that fueled the 20th century’s Atomic Age.
Now the Great Basin, covering Utah’s western lands, is home to deposits to various metals that could support the world’s transition to emission-free energy systems of the 21st century.
“This is a really unique, cool thing for Utah locally, but also with the deposit basically being comprised of indium, zinc and copper, all three of those are really essential commodities to the high-tech, carbon-neutral transitioning economy for the entire U.S.,” Mills said. “It might be like this weird little remote corner of Utah, but it actually is pretty impactful for the country as a whole.”
Because the U.S. depends on overseas sources for many critical minerals, there is a growing push to develop domestic supplies and Utah could play a key role. Already Utah is the only U.S. source of beryllium and could soon support important sources of helium, lithium and tellurium.
One major sphalerite deposit, located 100 miles southwest of Salt Lake City in the Fish Springs Range, is already under development by a Canadian mining company called American West Metals, which acquired the so-called West Desert Project early this year.
Known deposits in the West Desert contain enough indium to meet current U.S. demand for nine years, according to the UGS report. The element is usually recovered as a byproduct of zinc mining. Ore is refined into a compound known as indium-tin oxide, a transparent and colorless substance that is applied to glass surfaces.
Because it conducts electricity, indium-tim oxide, or ITO, is an integral component on almost all flat panel display screens, according to a 2020 report Mills wrote on Utah’s critical mineral reserves.
“There are very few substitutes for indium and ITO,” the report states. “Given the total import reliance for the United States, the ubiquity of indium requirements, and the lack of viable substitutes, indium is considered a critical mineral.”