Characteristics of Smithsonite:

Chemical Name: Zinc carbonate

Formula: ZnCO3

Colors: White, blue, green, yellow, pink, lilac, colorless

Structure: Hexagonal, trigonal

Hardness: 4-4.5

Specific Gravity: 4.3-4.5

Refractive Index: 1.62-1.85

Lustre: Vitreous to pearly

Streak: White

Locations: Namibia, Zambia, Mexico, Germany, Italy, Australia, USA

What is Smithsonite? 

Smithsonite can be various colors including yellow and pink, but blue-green is the most prized of all. Crystals are found occasionally- spectacular examples come from Tsumeb, Namibia – and sometimes faceted for collectors. Most gemstone material is cut en cabochon or carved into ornaments, but it is too soft for general wear as jewelry. Aside from its use as a gem, it is mined as a major source of zinc; it is thought that it may have provided the zinc component of brass in ancient metallurgy. One of the main sources is the Kelly Mine, New Mexico, USA.

Smithsonite was originally called by the umbrella name calamine – as in the anti-itch lotion used to treat skin problems, which contains the powered mineral. The English chemist and mineralogist John Smithson discovered that calamine was in fact three different minerals, and Smithsonite was named in his honor in 1832. The other two minerals were called hemimorphite and hydrozincite. Smithson also made the bequest that led to the establishment of the Smithsonian Institute.