Nickel (Ni) is a silvery-white metallic element known for its resistance to corrosion and ability to form robust alloys. As a transition metal, it possesses strength, ductility, and ferromagnetic properties, making it highly valuable across numerous industries. The recognition of nickel as a distinct chemical substance was a complex process spanning decades of metallurgical confusion and scientific investigation. This journey culminated in its official isolation in the mid-18th century.
The Historical Context of “Kupfernickel”
The story of nickel begins centuries before its scientific identification, rooted in the frustration of German miners in the Erzgebirge region of Saxony. These miners frequently encountered a reddish-looking ore, now known as niccolite (nickel arsenide, NiAs), which strongly resembled copper ore. When they attempted to smelt this mineral, they were met with two disappointing results: either no copper was produced, or the resulting metal was unusually brittle and unfamiliar.
Convinced that a mischievous force was preventing them from extracting the copper they expected, the miners assigned the ore a derogatory name. They called the substance Kupfernickel, a compound German word that translates to “copper goblin” or “devil’s copper.” This term reflected their belief that a mountain sprite, or “Nickel,” was tainting the valuable copper ore.
Isolation by Axel Fredrik Cronstedt
The challenge of Kupfernickel was eventually taken up by Baron Axel Fredrik Cronstedt, a Swedish mineralogist and chemist. In the early 1750s, Cronstedt began a systematic study of the perplexing ore. He started by dissolving the mineral in nitric acid, which yielded a green-colored solution, a common characteristic of copper compounds.
However, when Cronstedt attempted to precipitate metallic copper from the solution, no reaction occurred. This lack of expected chemical behavior indicated that the primary metal within the ore was not copper. He then subjected the ore to a powerful reduction process, heating the Kupfernickel with charcoal. This technique successfully separated a new, hard, silvery-white metal that exhibited ferromagnetic properties. Cronstedt recognized that he had isolated an entirely new “semi-metal,” distinct from iron, copper, and cobalt.
Confirmation and Classification as an Element
Cronstedt presented his discovery to the Royal Swedish Academy of Sciences in 1751 and 1754, initially naming the substance after the ore from which it was derived. He shortened the name from Kupfernickel to simply “Nickel” for the new element. The initial findings were met with considerable skepticism from the wider scientific community, with many chemists suggesting the substance was merely a complex alloy or a mixture of known elements.
It was not until two decades later that the elemental nature of nickel was definitively confirmed. In 1775, Swedish chemist Torbern Bergman succeeded in preparing a purer sample of the metal, which helped to dispel the lingering doubts. Bergman’s work demonstrated that the presence of arsenic and other contaminants had contributed to the initial confusion, solidifying Cronstedt’s claim of a new element.
Immediate Post-Discovery Applications
Following its confirmation as an element, nickel’s unique properties quickly became the subject of metallurgical experiments. The recognition of nickel’s ability to resist corrosion and enhance the strength of other metals drove its earliest applications. The first significant use was in the production of German silver, an alloy of copper, zinc, and nickel, which was valued for its silver-like appearance and resistance to tarnishing.
The presence of nickel in Chinese paktong, a form of cupronickel known for centuries, was finally recognized in Europe around 1822. In the early 19th century, scientists began to investigate the use of nickel to create improved steels. Michael Faraday was inspired by the rust-resistant nature of meteoric iron, which is naturally rich in nickel, and proposed its addition to steel to improve material properties. These early metallurgical insights laid the groundwork for the later, widespread adoption of nickel in coinage and industrial alloys.