Vanadium is a versatile transition metal widely distributed in the Earth’s crust, though not found in its pure metallic form in nature. It contributes significantly to modern industries, primarily by enhancing the strength and durability of steel alloys used in construction and aerospace. Beyond industrial uses, vanadium also plays a role in certain biological systems, with trace amounts found in various organisms.
Primary Mineral Deposits
Vanadium is primarily extracted from concentrated mineral deposits, with vanadiferous titanomagnetite (VTM) deposits being the most significant global source. These igneous-hosted deposits, formed from deep magmatic processes, are rich in magnetite and ilmenite containing vanadium. They typically contain 0.2 to 1 percent vanadium pentoxide (V2O5), though some areas can exceed 1.5 percent V2O5.
Sandstone-hosted vanadium deposits, often found alongside uranium, are another important source. These deposits, such as those on the Colorado Plateau in the United States, can have vanadium concentrations of 1 percent V2O5 or higher. Shale-hosted vanadium deposits, also known as vanadiferous black shales, are characterized by high carbon content and concentrations up to 1.7 percent V2O5. While many are not currently economic, they hold potential as future resources.
Vanadium also occurs in specific minerals like vanadinite (Pb5(VO4)3Cl), carnotite (K2(UO2)2(VO4)2ยท3H2O), roscoelite (a vanadium-rich mica), and patronite (a sulfide mineral). Vanadinite typically forms as a secondary mineral in arid regions, often associated with oxidized lead deposits. Carnotite is a uranium-vanadium mineral found in sedimentary rocks, while roscoelite is a green mica containing vanadium, sometimes found in gold-silver deposits. Patronite, a sulfide, was historically a commercial source of vanadium.
Global Occurrence and Major Producers
Vanadium resources are globally abundant, with world resources estimated to exceed 63 million tons. Production is concentrated in a few key countries. China, Russia, and South Africa are the leading producers, accounting for the majority of global vanadium output. Brazil also contributes significantly to world production and exports.
China is the largest producer, with a substantial portion of its vanadium coming from steel slag, a byproduct of steel production. Russia, the second-largest producer, also obtains much of its vanadium as a co-product from steel slag. South Africa’s production is largely from its extensive vanadiferous titanomagnetite deposits, particularly in the Bushveld Complex. Brazil also has notable magnetite deposits that contain vanadium. Australia holds the highest vanadium reserves globally, although a significant portion is not yet fully compliant with reporting standards.
Presence in Other Resources
Vanadium occurs as a significant component or byproduct in various other resources beyond primary mineral deposits. Fossil fuels are one such category, with vanadium concentrated in crude oil, particularly heavy crude oils where it is found in asphaltenes. Concentrations can range from 1,200 to 5,000 parts per million (ppm) in asphaltene, and vanadium can be recovered during petroleum refining.
Oil shale and coal also contain vanadium, with minor amounts produced as a byproduct from these carboniferous materials. The processing of these energy sources, including their combustion, can generate vanadium-bearing ash or residues amenable to recovery. Beyond fossil fuels, vanadium is present in bauxite deposits, which are aluminum ores, and certain iron ores. It is also found in phosphate rock deposits. During bauxite processing, vanadium can concentrate in the residual sludge, known as red mud.
Vanadium in the Environment
Vanadium is a naturally occurring element found widely throughout the environment, though typically in trace amounts. It is present in soil, with concentrations generally ranging from 10 to 500 parts per million. Its distribution in soil is influenced by factors such as redox potential, pH, organic matter, and microbial activity.
Vanadium is also found in natural waters, including rivers, lakes, and oceans. Streams and rivers typically contain 0.2 to 2.9 parts per billion (ppb) of vanadium, while coastal seawater has concentrations ranging from 0.3 to 2.8 ppb. Plants absorb vanadium from the soil, primarily accumulating it in their roots, with limited translocation to their shoots. While low levels can sometimes benefit plant growth, excessive concentrations can negatively affect plant health and development. Trace amounts of vanadium are additionally found in animal tissues.