Which major mineral resources are most susceptible to depletion? The Post Carbon Institute identifies antimony, bismuth, boron, chromium, copper, gold, rhenium, tin, and zinc as the major extractable mineral resources that are mostly likely to become scarce. These are often called peak minerals. According to Richard Heinberg in Peak Everything, the peak stage occurs when the highest possible rate of mineral production is taking place. The US Department of the Interior (https://www.doi.gov/) includes uranium on its list of critically scarce minerals as well. Crude nonmetallic rocks, used primarily for agriculture and construction, are not yet at the peak concern stage, as Tim Prior et al. note in their research study, “Resource Depletion, Peak Minerals and the Implications for Sustainable Resource Management.”
Perhaps one of the least known mineral resources on the list is antimony. Antinomy is used in batteries, ceramics, electrical cable sheathing, enamels, fire proofing additives, glass, metal alloys, pigments, and semiconductors. A detailed description of antimony is found in Manijeh Razeghi’s Antimony. First used by the ancient Egyptians in cosmetics and medical compounds, antimony became popular as a component for alloys in the 1500s. By the late 1700s, antimony alloys proved valuable in bullets and steam engines. The element is found in soils around the world, but extractable antimony deposits are primarily located in China and Russia; China produces the vast majority of the world’s mined antimony, according to the United States Geological Survey (USGS, https://pubs.usgs.gov). Global antinomy reserves are estimated to be depleted by 2060.
Bismuth, like antimony, is another lesser-known mineral resource and is found in all soils. Deposits of bismuth are found in two extractable forms: bismuthinite, which is high in sulfur, and bismite, which is an oxide compound of bismuth. These were mistakenly identified as lead from ancient times until the 1400s. Though it can be mined alone, Bismuth is typically extracted as a byproduct of lead mining. Traditionally used in pharmaceutical compounds and pigments, the mineral has found new applications in alloys and in electronic devices. Bismuth-Containing Compounds, by Handong Li and Zhiming Wang, describes many of these applications. Bismuth mining has increased almost ten-fold since 1900; today, approximately 80 percent comes from China. Owing to increasing consumption rates, it is estimated that bismuth reserves will decline steadily starting in 2020 and be depleted by 2060.
Boron is most noted for its industrial applications, but a growing body of research supports its use in medicine, as discussed in Evamarie Hey-Hawkins and Clara Teixidor’s Boron-Base Compounds. The Chinese and Persians used boron as a ceramic glazing agent starting around 300 CE; today, approximately half of the boron that is mined globally is used to make various glass and ceramic products. Boron has also made its way into cleaning agents, fertilizers, and semiconductors. Though found in all soils, deposits predominate in China, Russia, Turkey, and the US. Turkey has the vast majority of boron reserves, but the US is a large exporter of boron. The USGS claims that the current levels of global boron consumption will not result in depletion for another 250 to 500 years. The affordability of extracting boron is a bigger concern than boron depletion.
Chromium is not as common in the soil as other metals and is only found as chromite ore, according to Robert Krebs in The History and Use of Our Earth’s Chemical Elements. It is most abundant in South Africa, India, and Kazakhstan. The extraction of pure chromium from the ore is an extensive process that adds significantly to its cost. More information about chromium’s unique properties and applications is found in Swapan Haldar’s Platinum-Nickel-Chromium Deposits: Geology, Exploration and Reserve Base. Chromium is a highly valuable resource, most commonly used in chrome plating, pigments, and stainless steel. Discovered in France in 1797, it had few commercial applications until the early 1900s. Chromium extraction skyrocketed in 1950 and usage continues to increase. It is expected that chromium mining will decline starting in 2030 and reach depletion by 2100.
Copper ore has been surface mined and used by humans since approximately 9000 BCE. It was refined into a pure metal about 5000 BC and replaced many of the uses of nonmetallic minerals during the Copper Age (3000 BCE). Today, copper is a key material used for electronic devices, transportation equipment, and construction materials, as discussed in Copper, by Günter Joseph. Copper consumption is expected to rise as these three commercial sectors grow across the globe. Copper deposits are found in many regions, but the largest reserves are in Australia, Chile, Mexico, and Peru. China and the US are the largest copper consumers. Estimates indicate that copper reserves will steadily decrease by 2050 and be depleted around 2100.
The first evidence of gold’s use by humans dates back to 40,000 BCE, but historians trace its value as a prized resource to Egypt around 3000 BCE, as discussed in Prehistoric Gold in Europe, by Giulio Morteani and Jeremy Northover. Trace amounts are found around the world, but most of the world’s gold reserves are located in South Africa. Recently, South African gold mining has been exceeded by Australia, China, Canada, Peru, Russia, and the US. China is currently the world’s leading gold producer. Although gold has many commercial uses, it is most valued in jewelry and monetary exchange. Along with iron, gold is considered one of the most historically important metals, as discussed in A History of Gold and Money: 1450–1920, by Pierre Vilar. Experts predict that gold extraction will rise until 2050 and become depleted around 2060.
Rhenium sounds more like a disease than a transition metal element listed on the periodic table. The existence of rhenium was predicted in 1912, but it was first discovered in platinum ore in 1925. It is very rarely found in soil, but is prevalent in a lustrous rock called columbite, as described by J. G. F. Druce in Rhenium. According to the USGS, most rhenium is collected from copper mining by-products. Rhenium is used for the production of lead-free gasoline and in lightweight alloys. Most of the world’s rhenium mining occurs in Chile, followed by the US. Rhenium extraction is expected to peak in 2100 and rapidly decline to depletion by 2200.
Tin has been used in the production of bronze since 3500 BC, and its great utility for fashioning many objects heralded the Bronze Age. According to Tin and Global Capitalism, 1850–2000, edited by Mats Ingulstad, Andrew Perchard, and Espen Storli, tin has played a critical role in warfare, food preservation, and electronic devices. Newer applications abound in the production of superconducting materials. The major tin producers are China, Indonesia, and Peru; the greatest tin reserves are found in Southeast Asia and China. Tin extraction is expected to increase until 2025 and steadily decline to depletion by 2100.
Surprisingly, uranium is a common component of many soils and is also found in seawater, as Robert Lauf mentions in Mineralogy of Uranium and Thorium. There are several forms, or isotopes, of uranium ore. The isotope uranium-235 is the most valuable because of its utility in nuclear fission reactors. Discovered in Germany in 1789, it was initially used as a pigment in ceramics and glass items; its radioactive properties were discovered in 1896. Its proposed use as a treatment for cancer in the early 1900s led to an increase in uranium mining. Uranium became a more highly valued resource when scientists were able to control nuclear fission reactions, a development which fundamentally changed the nature of energy production and warfare. The largest high-grade, or high concentration, uranium deposits are found in Australia, Russia, Canada, Niger, and Kazakhstan. The US has few uranium resources. Global reserves of uranium are expected to decrease starting in 2040 and become depleted by 2100.
Zinc has a moderate abundance in many soils and is commonly found in ore deposits called sphalerite. Zinc was discovered around 3000 BCE in the Middle East and was later used as a component of brass. Brass proved to be a valuable alloy because of its malleability and resistance to corrosion, as discussed in Howard Mendenhall’s Understanding Copper Alloys. It also finds uses in a variety of industrial and consumer products. Zinc is a common component of soils, and zinc mining is distributed around the world. Currently, Australia and China extract the greatest amounts of zinc. Zinc extraction is predicted to steadily increase until around 2040 and quickly decline to the point of depletion in 2100.
Even the three most abundant mineral resources—aluminum, feldspar, and silica—may eventually face depletion. According to Nicholas Arndt, Stephen Kesler, and Clément Ganino in Metals and Society, aluminum is abundant in most soils as well as bauxite. In Feldspar, editors Francis Whitmore and Jorge Escamilla note that non-metallic mineral feldspar composes over half the Earth’s crust. Silica is found in almost all rocky material; in its purified form it is made into glass and hardening agents, as discussed in Crystalline Silica, published by the Society for Mining Metallurgy and Exploration. Yet concentrated reserves of these three minerals are being rapidly depleted, while large volumes are quarried as untreated rocks. The untreated materials form a vast market and are sold in the aggregates market for building materials and road construction. Rock quarries, common throughout the world, are multiplying. Purified aluminum, feldspar, and silica are also being harvested heavily from mining operations. The USGS is confident that no shortage of quarry rock is expected to occur before 2050. However, it is quite possible that the world supply of aggregate rocks could begin decreasing rapidly starting in 2100.
The History and Use of Our Earth's Chemical Elements by 
Copper: Its Trade, Manufacture, Use, and Environmental Status by 
Prehistoric Gold in Europe: Mines, Metallurgy and Manufacture by 
Metals and Society: An Introduction to Economic Geology by 
