40 Fun Facts About Cobalt

Cobalt's name is traditionally traced to a German word for which mischievous creature of mining folklore?

Goblin, or Kobold in German, was the miners' culprit for ore that looked rich yet gave up no silver and released poisonous fumes in the furnace.

Which essential nutrient, found in meat, eggs and dairy, is built around a single atom of cobalt?

Vitamin B12 is the only vitamin that contains a metal atom. Only bacteria and archaea can make it, so every animal depends on microbes for its supply.

Which central African country mines well over half of the world's cobalt, mostly in its Katanga copper region?

DR Congo dominates the metal so thoroughly that a 2018 investment report likened it to the Saudi Arabia of the electric vehicle age.

In the 1960s, cobalt salts added to which drink to steady its foam caused serious heart disease in heavy drinkers?

Beer drinker's cardiomyopathy was the name doctors gave the new illness after it struck heavy drinkers in Canada in 1966.

Which 1964 Stanley Kubrick satire features a Soviet doomsday machine built from cobalt-laced nuclear bombs?

Dr. Strangelove calls its doomsday material Cobalt-Thorium G, borrowing a real 1950 thought experiment about a bomb designed to spread deadly fallout.

A cobalt chloride solution is a classic recipe for which spy tool, turning blue only when heated?

Invisible ink made with the salt dries almost colorless, shows up when warmed, and then fades again, so one message can vanish and return.

Which video game company colored its mascot Sonic the Hedgehog to match its own cobalt blue logo?

Sega picked the hedgehog's color to echo its logo, then modeled his shoes on Michael Jackson's boots.

Cobalt lends its name to a famous blue pigment, but what color is the pure metal itself?

Silvery gray, with at most a faint bluish tinge, is the metal's true look. The vivid blue appears only once its compounds are fired into glass, glazes and paint.

Scientific analysis shows Vincent van Gogh brushed cobalt blue into the swirling sky of which 1889 painting?

The Starry Night owes its glowing stars and moon to a rarer choice still: Van Gogh combined Indian yellow with zinc yellow.

Most cobalt mined today goes into the rechargeable phone and car batteries named for which lightweight metal?

Lithium-ion cells in phones and laptops still rely on cobalt-rich cathodes, while many electric cars have moved to recipes that need far less of it.

Cobalt and iron are two of the three common metals that are strongly magnetic at room temperature; which is the third?

Nickel completes the trio, though cobalt holds its magnetism at higher temperatures than either partner, staying magnetic up to about 1,115 °C.

Miners once feared cobalt ores because smelting them released deadly fumes of which notorious poison?

Arsenic is bound into the main cobalt ores, so roasting them sent a toxic oxide up the chimney and gave the rock its cursed reputation.

Dry cobalt chloride test paper is blue; which color does it turn when it touches moisture?

Pink is the color of the salt once it takes up moisture, and the switch reverses on drying, so the same strip can be used again and again.

Cobalt oxide gives the trademark blue to the tin-glazed pottery of which Dutch city?

Delft potters turned to the style after 1620, when the death of China's Wanli Emperor interrupted the supply of imported porcelain to Europe.

Heat-resistant cobalt superalloys were prized after World War II for the turbine blades of which machines?

Jet engines made high-purity cobalt so sought after that the United States began prospecting for the metal at home once the war ended.

Cobalt belongs to which family of elements in the middle block of the periodic table, alongside iron and copper?

Transition metals often form brightly colored compounds, the trait behind cobalt's long career in glass, glazes and paint.

The cobalt in Earth's crust was originally forged in which violent cosmic events?

Supernovae also shine because of the element: the decay of freshly made radioactive cobalt keeps an exploded star glowing for months.

Uncombined cobalt metal is found on Earth's surface almost only inside which objects, alloyed with iron?

Meteorites keep the metal locked in iron alloys, shielded from oxygen and damp; everywhere else in the crust it exists only in chemical compounds.

Cobalt from desert oases colored deep blue glass more than 3,000 years ago in which ancient land?

Egypt's glassmakers of the Eighteenth Dynasty drew their cobalt from alum deposits in the oases of the Western Desert.

Which Japanese electronics company first sold rechargeable batteries with a cobalt oxide cathode, in 1991?

Sony's cell became the template for the battery in nearly every phone and laptop since, built on a cathode identified at Oxford in 1980.

Which Swedish chemist isolated cobalt around 1735, becoming the first named discoverer of any metal?

Georg Brandt proved the new metal with experiments rather than tradition, and he spent his later career exposing fraudulent alchemists.

Before cobalt was identified, the blue it gives glass was wrongly credited to which other metal found in the same ores?

Bismuth turns up in the same ores, so it took the credit until 18th-century experiments showed that only the newly isolated metal turned glass blue.

Radioactive cobalt-60 gives off which penetrating radiation, used to sterilize medical supplies and irradiate food?

Gamma rays from cobalt-60 made at a single Canadian power station, Bruce, sterilize a large share of the world's single-use medical devices.

Chemistry students view flame tests through cobalt blue glass to filter out the yellow glare of which element?

Sodium, even in traces, burns a strong yellow that swamps other colors; the glass blocks it so fainter violet and blue flames show through.

Cobalt-poor volcanic soils caused 'bush sickness' in cattle in which country in the early 20th century?

New Zealand's North Island plateau lacked the trace metal; farmers later beat such shortages with cobalt bullets, dense pellets that lodge in an animal's stomach.

The town of Cobalt in which Canadian province boomed after silver was found beside a new railway in 1903?

Ontario's boomtown was the world's fourth-highest silver producer by 1910, and prospectors trained there went on to find gold at Kirkland Lake and Timmins.

The cobalt that made Chinese blue-and-white porcelain possible in the 14th century was imported from which land?

Persia's ore was known in China as Islamic blue, and it stayed the most expensive cobalt even after local deposits were opened in the 16th century.

In 1818 watercolorist John Varley recommended cobalt blue for skies as a substitute for which prized older pigment?

Ultramarine had to be painstakingly extracted from the stone lapis lazuli, which made a factory-made blue a welcome alternative for painting skies.

Which metal is alloyed with cobalt in the tough, corrosion-proof implants used for artificial hips and knees?

Chromium and cobalt together resist corrosion so well that a pair of hip implants fitted in England in 1948 were still in place 67 years later.

Cobalt-based catalysts help oil refineries strip which element from fuel, cutting the pollution that causes acid rain?

Sulfur is pulled out by a catalyst that pairs cobalt with molybdenum, the chemistry behind today's ultra-low-sulfur diesel.

Which animation pioneer was treated with cobalt-60 radiation for lung cancer in 1966, weeks before his death?

Walt Disney received what was then standard care: cobalt machines dominated radiotherapy until linear accelerators began replacing them in the 1970s.

Which sky-blue artists' pigment, made from cobalt and tin, shares its name with Pantone's first Color of the Year?

Cerulean reached painters as a watercolor around 1860 and caught on in the 1870s, once it was also sold as an oil paint.

Blaafarveværket, once the supplier of most of the world's cobalt pigments, operated in which Scandinavian country?

Norway's Blue Colour Works supplied 80 percent of the world market at its peak, and its old mines are now a large open-air museum.

Which American chemist, later the namesake of element 106, co-discovered radioactive cobalt-60 in 1938?

Glenn Seaborg found the isotope with John Livingood, and 25 years later he personally dedicated a hospital's new cobalt treatment unit.

Which Hungarian-born physicist described the cobalt bomb in a 1950 radio broadcast as a warning about doomsday weapons?

Leo Szilard never wanted one built: he meant to show that nuclear technology would soon be able to end human life on Earth.

Physicist Chien-Shiung Wu used chilled cobalt-60 in 1956 to overturn which supposed law of nature?

Conservation of parity fell so decisively that the two theorists who proposed the test won the 1957 Nobel Prize, while Wu, who ran the experiment, was left out.

Which pigment, made by grinding cobalt glass to powder, colored many European paintings of the 15th to 17th centuries?

Smalt loses its color over time, so it is usually discolored in surviving pictures and is little used by painters today.

Which rare-earth element is paired with cobalt in powerful magnets that keep working at very high temperatures?

Samarium magnets, developed in the 1960s at a US Air Force base, rival neodymium types in strength but tolerate far more heat.

Which American illustrator built his luminous skies on a cobalt blue base, inspiring a shade named after him?

Maxfield Parrish coated that base with thin alternating layers of oil and varnish, a time-consuming method he invented himself.

Bou-Azzer, one of the few places where cobalt is mined as the main product, lies in which North African country?

Morocco's mine is a rarity: nearly all other cobalt is recovered as a by-product of digging for more plentiful metals such as copper.