The Mineral Named for Our Benefactor

Smithsonite is a mineral named after James Smithson, the founding donor of the Smithsonian. He was an English scientist who lived c. 1765-1829.

In a secondary clause in his will, he left his fortune to the United States of America—a place he never visited—to create “an establishment for the increase and diffusion of knowledge among men.”

Smithson was a well-regarded scientist and dedicated his life to investigating the natural world, traveling in Europe to find crystals and minerals to discover and classify their properties.

This luminous mineral is zinc carbonate (ZnCO3), one of a group of ores that yield the metal zinc. It was named smithsonite in honor of James Smithson because it was he who first identified the mineral in 1802.

This smithsonite specimen, a gift from Mr. Leonard Wilkinson, is from the preeminent smithsonite locality in the United States: the Kelly mine in Magdalena district, Socorro County, New Mexico. It is 11 cm across, 7.5 cm high.

Smithsonite is typically found as botryoidal masses (having a shape reminiscent of a cluster of grapes) and is only rarely found as well-formed crystals.

The gems pictured here show a range of colors and are all from the United States. The yellow cabochon is from Arkansas, and the blue cabochon is from New Mexico.

Gem quality smithsonite is very rare and typically exhibits a semi-transparent bluish-green color with beautiful luster. This faceted green gem is from Arizona.

When Smithson began to conduct his experiments on zinc ores, there was much confusion surrounding the mineral which at that time was known generally as calamine. Miners and metalworkers had long known that some kinds of calamine produced zinc, while other specimens—which contained zinc and appeared identical—did not. Smithson’s analysis revealed that what was called “calamine” was not in fact a single substance but essentially two distinct minerals: zinc carbonate (which was later named smithsonite) and zinc silicate (which came to be called hemimorphite, seen here). He identified the carbonate as a good ore for zinc and the silicate as a poor one.

Smithson’s analysis was published as an article in the prestigious Philosophical Transactions of the Royal Society and was widely praised. It was seen as a model for applying chemistry to the study of mineralogy, which were mostly separate disciplines at this time.

Although he didn’t call attention to it, Smithson’s paper also contained a technique that would have been of great practical benefit to miners and brass manufacturers; the use of a blowpipe to conduct chemical analysis.

One of the problems with zinc ores, especially the forms of calamine that Smithson identified, was that they were often difficult to tell apart. Smithson developed a simple test that miners could use to identify which was which. It used a small but powerful tool called a blowpipe, an oil lamp, and a piece of charcoal.

This Plattner's blowpipe was made to be used for long periods without a break.

The trumpet shaped mouthpiece helped keep the lips from getting tired.

A reservoir on the end collected saliva. It also had a small platinum tip, which kept it from melting when held in a flame for long periods.

The blowpipe was a difficult tool to master, and Smithson was widely admired for his skill in using it. In order to maintain a steady flame, one had to breathe in through the nose while at the same time blowing out through the mouth. One also had to develop a familiarity with a wide range of effects in order to understand how particular materials reacted to the flame.

Smithson was also known for his manipulation of miniscule quantities. He boasted of experimenting on “particles little more than visible” and took great pleasure in “the great beauty of deriving knowledge from so diminutive a source.”

His work on the zinc ores exemplified not only his technical skill but also the depth of his understanding, both of which are still honored today through the mineral smithsonite.

Smithsonian Castle Collection
Credits: Story

Adapted by
Marc Bretzfelder
Smithsonian Office of the Chief Information Officer

From the online exhibit
Smithsonite
by the
National Museum of Natural History

Credits: All media
The story featured may in some cases have been created by an independent third party and may not always represent the views of the institutions, listed below, who have supplied the content.
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