Smithsonite, or zinc carbonate, is a favorite among mineral collectors for its range of pleasing colors and often well-developed, botryoidal form. Most collectors agree that smithsonite’s most striking color is the saturated, robin’s-egg blue of the lustrous, translucent specimens from Magdalena, New Mexico.
Steve Voynick is a science writer, mineral collector, and former hardrock miner, and the author of guidebooks like Colorado Rockhound ing and New Mexico Rockhounding.
Smithsonite is also interesting for its unusual historical connection, which is rooted in “calamine,” a mineral that scientists initially believed to be zinc oxide. But in 1803, English chemist James Smithson demonstrated that calamine was actually a mix of three zinc minerals—an oxide, a carbonate, and a silicate. Smithson’s success in chemically differentiating oxide and carbonate minerals was a major advancement in qualitative mineralogy. In 1832, calamine’s zinc-carbonate component was formally named “smithsonite” in his honor. But Smithson’s legacy was destined to go much further.