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The mineral, Smithsonite, is named for him.

The minerals containing lead are principally galenite or lead sulphate, cerussite or lead carbonate; while the zinc is contained in the minerals, sphalerite or zinc sulphide, calamine or zinc silicate, smithsonite or zinc carbonate, etc.

The phenomenon was first discovered in the tourmaline, and it is observed, speaking broadly, only in those minerals which are hemimorphic, that is, where the crystals have different planes or faces at their two ends, examples of which are seen in such crystals as those of axinite, boracite, smithsonite, topaz, etc., all of which are hemimorphic.

Beudant in 1832 restricted the name calamine to the hydrous silicate and proposed the name "smithsonite" for the carbonate, and these meanings of the terms are now adopted by Dana and many other mineralogists.

In his time, the native carbonate and the silicate of zinc were confounded as one species under the name calamine; but his researches distinguished between the two minerals, which are now known as Smithsonite and Calamine, respectively.