Smithsonite

Smithsonite (a.k.a. "turkey fat" or "zinc spar") is the mineral form of zinc carbonate (ZnCO3). Historically, smithsonite was identified with Hemimorphite before it was realized that they were two different minerals. Smithsonite was named in 1832 by François Sulpice Beudant in honor of English chemist and mineralogist James Smithson (c.1765–1829), who first identified the mineral in 1802. It occurs as a secondary mineral in the weathering or oxidation zone of zinc-bearing ore deposits.