On November 26, 1801, the discovery of a new element – columbium – was announced. Forgotten for decades owing to a confusion, it was rediscovered in 1844, this time as niobium. A.S.Ganesh gives you the convoluted story of discovery, rediscovery and naming of niobium.

The stories behind the discovery of many elements in the periodic table make for a fascinating read. Top among them should be the element with the atomic number 41, a shiny, white metal, solid at room temperature and known now as niobium, with the atomic symbol Nb. For niobium’s story spans over centuries, with twists and turns befitting any good piece of fiction.

This tale begins with a mineral called columbite, the occurrence of which in the United States was presumably discovered by John Winthrop the Younger, an early governor of the Connecticut Colony with an avid interest in its mineral resources. Decades after the ore was discovered in the 17th century, samples were donated to England by members of Winthrop’s family.

Holds its secrets

The ore specimen made its way to Sir Hans Sloane’s (Irish physician, collector and naturalist) collection and it thus became part of the British Museum in the 18th century. And it sat there till the turn of the century, waiting to reveal its secrets.

It was under these circumstances that Charles Hatchett, a self-educated scientist and analytical chemist, came upon the ore at the British Museum while examining and arranging minerals. On checking upon Sir Hans Sloane’s catalogue, the specimen was merely described as a “very heavy black stone with golden streaks, which proved to be yellow mica, and it appeared that it had been sent…to Sloane by Mr. Winthrop, of Massachusetts.”

By obtaining samples from the museum and subjecting it to exhaustive chemical analysis, Hatchett was able to come to the conclusion that columbite contained a new element. Even though Hatchett wasn’t able to isolate the element, he read to the Royal Society about his discovery of a new element, which he named columbium, on November 26, 1801.

Tantalisingly close

In 1802, Swedish chemist Anders Gustaf Ekenberg discovered the element Tantalum in minerals obtained from Ytterby, Sweden. Columbium and tantalum are extremely similar chemically, difficult to isolate and almost always found together.

When William Hyde Wollaston, an English chemist, became suspicious that columbium and tantalum might well indeed be the same element, he started investigating the ores from which these elements had been discovered. After sufficient experimental work in which he compared the physical and chemical properties of both materials, he concluded in 1809 that both elements were in fact the same.

As Hatchett, who came from an affluent family and had taken over the family’s coach-building business following his father’s death, had effectively given up on science completely by this time, there was no one to defend his discovery and Wollaston’s opinion prevailed predominantly.

Rose’s rediscovery

It remained the case till 1844, when German mineralogist and analytical chemist Heinrich Rose, working with samples of columbite and tantalite, produced two new acids, which were very similar, but separate. He named the acid obtained from columbite as niobic acid and its metallic component as niobium – after Niobe, one of the children of Tantalus (after which tantalum is named) in Greek mythology. Rose had in effect rediscovered columbium and renamed it niobium.

In the decades that followed, it was established beyond any doubt that niobium is in fact an element of its own accord and it was also isolated in metallic form. Obtained primarily from columbite and pyrochlore these days, niobium is used in jewellery and superconductivity research, especially in making superconductive magnets.

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What is it called now anyway?

Even though the International Union of Pure and Applied Chemistry (IUPAC) officially adopted the name niobium for the element in 1950, it is still referred to by both of its names – columbium and niobium.

While the element was called niobium in Europe following Rose’s rediscovery, the Americans had continued calling it columbium. Though niobium became the officially accepted name following the decision by IUPAC, those in North America continue to call it columbium.

The fact that it was named after Columbia, the female personification of the United States, is probably a reason why Americans still stick to that name.

Even in the Mineral Commodity Summaries 2018 from the U.S. Department of the Interior and the U.S. Geological Survey, niobium is mentioned with columbium in brackets on many occasions.