With an understanding that something doesn’t just come from nothing, we explored the base materials used for the creation of plastics used in the 3D printing industry. Similarly, the metals that make up 3D printing don’t appear out of thin air. Instead, they are physical resources on a finite planet. While all metals are limited in supply, some are far rarer and their use will ultimately result in supply issues.
We’ve already covered how metal 3D printing materials are processed into printable powders and the variety of metals in use by the industry today. But, where do all of our 3D printing metals come from? We will look at the world’s supply of some of the most prominent or important metals in the 3D printing industry, relying on the United States Geological Survey (USGS) for our numbers. Generally, we won’t list every country from which minerals are produced, but just those with the highest production rates.
Titanium is one of the most important metals in the 3D printing industry. It is seventh-most abundant metal in the Earth’s crust, found in 784 different igneous rocks, but the two with economic importance, rutile and ilmenite, are difficult to find in high concentrations. The countries producing the most ilmenite are South Africa (1.3 million tons), Australia (900,000 tons), China (800,000 tons), and Mozambique (550,000 tons). The highest rutile production comes from Australia (450,000 tons), Senegal (160,000 tons), Ukraine (90,000 tons) and Kenya (80,000 tons).
A custom titanium 3D-printed cranio-maxillofacial implant made using EBM technology. (Image courtesy of Arcam.)
With total titanium reserves in ilmenite and rutile estimated to be over 930 million tons, Australia has the highest ilmenite reserves at 250 million tons, followed by China with 220 million tons, and Australia also has the highest rutile reserves at 29 million tons, followed by Kenya at 13 million. In comparison, the U.S. has combined ilmenite and rutile reserves of 2 million tons, just a little more than Vietnam and slightly less than Ukraine.
Aluminum is the most abundant metal in the Earth’s crust and the second most widely used metal globally, after iron. Because of its chemical reactivity, finding aluminum as a native metal is rare. Instead, it is most often extracted from the sedimentary rock bauxite. World bauxite deposits are estimated to be between 55 and 75 billion tons, with 32 percent in Africa, 23 percent in Oceania, 21 percent in South America and the Caribbean, 18 percent in Asia and 6 percent throughout the rest of the globe.
As of 2017, Australia was the largest miner of bauxite with 83 million tons produced that year, followed by China at 68 million tons. Guinea has the largest reserves at 7.4 billion tons, followed by Australia with 6 billion and Vietnam with 3.7 billion. The U.S. did not list how much bauxite it produced and has the least amount in reserves at 20 million tons.
Steel is an alloy made up of iron and carbon. The fourth most common element in the Earth’s crust, 98 percent of mined iron is used to make steel. In order of rocks and minerals with the highest iron oxide content are magnetite, hematite, goethite, limonite and siderite. Ores with more than 60 percent magnetite or hematite, known as “natural” or “direct shipping” ores, can be placed directly into a blast furnace to create “pig iron”, using coking coal and limestone. Since it is too brittle for use due to higher levels of carbon, pig iron is continually reprocessed to create steel, with additional elements added in to produce different grades.
The largest producer of iron ore in 2017 was Australia with 545 million tons, followed by Brazil (280 million tons), China (210 million tons), and India (120 million tons). The U.S. produced 28 million tons, more than Canada, but less than Iran. Australia has the highest iron reserves at 24 million tons, followed by Russia (14 million tons) and Brazil (12 million tons).
While steel can be made from iron ore, it is also one of the most-recycled materials on the planet, with a recycling rate of 60 percent globally.
While cobalt can be extracted from its ores, cobaltite, erythrite, glaucodot and skutterudite, it is primarily produced as a byproduct of nickel and copper mining. Unlike steel/iron, cobalt is a rare metal.
A bridge framework 3D-printed in CE-certified cobalt chrome with Renishaw’s LaserPFM dentistry 3D printing. (Image courtesy of Renishaw.)
The Democratic Republic of Congo (DRC) produces 63 percent of the world’s cobalt, with 64 million tons produced in 2017. For a comparison, the next highest production, from Russia, comes in at only 5.6 million tons. Total world reserves of cobalt are estimated to be only 7.1 billion tons, with about half (3.5 billion tons) held by the DRC.
Nickel is very rare, mined most often from laterite and sulfide deposits. In 2017, the largest producer of nickel was Indonesia at 400,000 tons, followed by the Philippines (230,000 tons), New Caledonia (210,000 tons) and Canada (210,000 tons). Total world reserves of the metal stand at 74 million tons, with the largest located in Australia (19 million tons) and Brazil (12 million). The U.S. has just 130,000 tons in reserves and produced 23,000 tons in 2017.
Copper can be found in very small quantities bound up with other valuable minerals within the following ores, in order of greatest copper content: cuprite, chalcocite, digenite, covellite, bornite, malachite, azurite, tennantite, dioptase, chrysocolla, chalcopyrite and tetrahedrite. Chile is the largest producer of copper, with 5.3 million tons produced in 2017, followed by Peru (2.4 million tons), China (1.9 million) and the U.S. (1.3 million). Chile has the largest reserves at 170 million tons, followed by Australia (88 million), Peru (81 million), Mexico (46 million) and the U.S. (45 million).
Gold is most often found as a native metal, usually with silver and often with other minerals like quarts and pyrite. Historically, South Africa was the largest producer of gold until 2006, with its peak occurring during apartheid in the 1970s. Now, the biggest supplier of gold is China (440,000 tons), followed by Australia (300,000 tons), Russia (255,000 tons) and the U.S. (245,000 tons). Total reserves are estimated to be about 54 million tons, with Australia (9.8 million) maintaining the most, followed by South Africa (6 million), Russia (5.5 million) and the U.S. (3 million).
Very rare, platinum is often found as a native metal, frequently in alluvial deposits, and as an alloy with other platinum-group metals (PGMs)—ruthenium, rhodium, palladium, osmium, iridium—and iron. PGMs can also be found as sulfides in nickel and copper deposits.
South Africa is far and away the largest producer of platinum, with 140 million tons produced in 2017, followed by Russia (21 million), Zimbabwe (15 million), Canada (12 million), and the U.S. (3.9 million). South Africa also has the largest reserves of PGMs at 63 billion tons, followed by Russia (3.9 billion) trailing by a large distance, Zimbabwe (1.2 billion), the U.S. (900 million), and Canada (310 million).
Extremely rare, tantalum always occurs with niobium in the minerals tantalite, columbite and coltan (a mixture of tantalite and columbite). In 2017, Rwanda (390,000 tons) and the DRC (370,000 tons) were responsible for almost 60 percent of mined tantalum, followed by Nigeria (190,000 tons), Brazil (100,000 tons), China (95,000) and Ethiopia (60,000).
According to Five Colleges professor Michael Klare, “one-fifth of the world’s tantalum supply comes from small-scale, clandestine mining operations in the eastern Congo that connect to world markets through circuitous routes, often going through Rwanda. (Indeed, it is generally believed that Rwanda is not actually a significant producer in its own right, and functions only as an export platform for tantalum covertly extracted elsewhere.)”
World reserves of tantalum are estimated to be only 110 million tons, with Australia maintaining 78 million tons and Brazil 34 million tons. Some estimate that, at current extraction rates, there are only 50 years left of tantalum reserves.
Tungsten, or wolfram, is a rare metal found most often in wolframite and scheelite. China is the world’s largest miner of tungsten, having produced 79 million tons in 2017, followed by Vietnam (7.2 million tons), Russia (3.1 million tons), Bolivia and the UK (at 1.1 million tons each). Current world reserves stand at 3.2 billion tons, with China holding the most at 1.8 billion tons, followed by Russia (160 million tons) and Vietnam (95 million tons).
Looking at the sources of these metals reveals some interesting details. If you feel like reflecting on your place in the universe, you might be fascinated by the cosmological origins of all of these materials in the hearts of stars whose formation can be traced back to the Big Bang.
From a much more worldly view, the metals discussed here provide insight into industry at large, geopolitical affairs and overall metal reserves. A prime example is tantalum and the DRC. The United Nations cited coltan smuggling and export as playing an important role in the war in the DRC, which included arms and training from the U.S. and led to over five million deaths in 1998. Today, tantalum is considered a conflict mineral with its mining in the DRC associated with human rights violations, child labor, and exposure to toxins (we won’t go into all of the issues here, but all mining brings with it a host of social and environmental concerns).
Tantalum is also associated with many modern technologies, such as cell phones and computers, which means that the known supply will continue to diminish as more such products are manufactured.
While this is just one example of a rare metal used in 3D printing, one can see how geopolitical affairs might play into metal sourcing at a given time in the future. When different governments manage a large proportion of the supply of a certain material, not only can entire industries be impacted but conflicts could also potentially arise.
For instance, due to China’s dominance of the rare earth metals market, the market is heavily dependent on the decisions made by the Chinese government. The government has regularly decided to reduce its exports of rare earth metals, causing prices to fluctuate and potentially affecting industries, such as the production of wind and solar power, that rely on those metals. As green energy is increasingly adopted to replace fossil fuel infrastructure, not only can wind and solar production be shaken by such decisions, but so can intergovernmental talks and even the climate itself.
The very rare platinum, for example, is key to making catalytic converters, which are necessary to convert carbon monoxide, nitrogen oxide, and other emissions into water vapor. Therefore, the metal is vital for making fossil fuel-driven cars cleaner for the environment while new green transportation is put in place. Moreover, those betting on hydrogen fuel cell technology should know that platinum is also important as a catalyst in that technology.
Two countries dominate platinum production: Russia and South Africa. If any geopolitical issues arise with those countries, supplies could suddenly be cut off and result in general upsets disruption in various industries.
Supply shortages could either be a boon to 3D printing, which uses only the material necessary to fabricate a part with little waste, or a disadvantage, given the niche applications that 3D printing serves.
Future Material Supplies
If shortages do occur, mining companies are already looking to new sources, including the Arctic, the moon and asteroids. For example, 370 miles north of the Arctic Circle in Baffinland, Canada, a mine was opened to recover iron ore and ship it around the world, requiring icebreaker freighters to carry the ore through the region’s glacial waters.
When Earth supplies of metals become too rare, space offers its own sources of metal deposits. All of the metals on this list can be found in asteroids and there are already a handful of companies looking to figure out how to land on those flying rocks, extract the materials and ship them back to Earth. It’s possible that the Moon, too, has valuable minerals, which brings new significance to a second trip to the Moon by the U.S.